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Talc is also used on the skin as a moisture absorber, hence its use on baby's bottom.
In a cream or balm, Talc also helps reduce the feeling of oiliness.
Talc is also used as an anti-sticking substance and anticaking agent in food products and dispersing agent in animal feed and fertilizers.
CAS Number: 14807-96-6
EC Number: 238-877-9
Molecular Formula: H2Mg3O12Si4 / Mg3(OH)2Si4O10
Molecular Weight: 379.27 g/mol
SYNONYMS:
Talc, Talcum, Soapstone (Powder), Magnesium Silicate Hydrate, Steatite, French Chalk, Huashifen, Pulvis talci, STERITALC, 7SEV7J4R1U, INS NO.553(III), INS-553(III), E-553(III), Potstone, Cubic Master, Sterile Talc, non-fibrous talc, Steritalc 2g, Steritalc 3g, Steritalc 4g, Pan Aromas Baby, Crown Talc Z, Health Smart Baby, Wart Remover Patch, Talc, non-asbestos, Natures Choice Baby, non-asbestiform talc, Sterile Talc Powder, Cimflex 606, Beaver White 325, Crown Talc W 83, CT 8 (mineral), B 9 (talc), RefChem:932528, Nekvnro Wart Remover Patch, Sclerosol Intrapleural Aerosol, 238-877-9, 14807-96-6, Agalite, Alpine talc USP, bc 127, Asbestine, CI 77718, Desertalc 57, Emtal 596, Fibrene C 400, French chalk, Lo Micron talc USP, bc 2755, Mistron 2SC, Mistron frost P, Mistron RCS, Mistron Star, Mistron super frost, Mistron vapor, MP 12-50, MP 25-38, MP 45-26, Nonasbestiform talc, Nonfibrous talc, Purified talc, Sclerosol, Snowgoose, Steawhite, Supreme dense, Talc, TALC (Mg3H2(SiO3)4), Talc (powder), Talc powder, Talcum Powder, Talc [JAN], TALC [VANDF], TALC [HSDB], TALC [FCC], TALC [WHO-DD], TALC [WHO-IP], TALC [II], TALC [MI], PULVIS TALCI [CHP], TALC [EP IMPURITY], TALC [ORANGE BOOK], TALC [EP MONOGRAPH], TALC [USP MONOGRAPH], PURIFIED TALC [MART.]
Talc is a hydrated magnesium silicate.
Talc is the world’s softest mineral.
Although all talcs share the same basic properties – platyness, chemical inertness, softness, water repellency and an affinity for organic substances – each talc orebody has its own features, so no two talcs are quite the same.
Talcs’ unique properties provide specific functions in a myriad of products and processes.
The magazines we read, the plastics in our cars and houses, the paints we use and the floor tiles we walk on are just some of the products that talc “brings to life”.
Talc is the world’s softest mineral.
Although all talc ores are soft, platy, water repellent and chemically inert, no two talcs are quite the same.
Talc is a vital part of everyday life.
The magazines we read, the polymers in our cars and houses, the paints we use and the tiles we walk on are just some of the products that talc enhances.
Talc is a hydrated magnesium sheet silicate with the chemical formula Mg3 Si4 O10 (OH)2.
The elementary sheet is composed of a layer of magnesium-oxygen/hydroxyl octahedra, sandwiched between two layers of siliconoxygen tetrahedra.
The main or basal surfaces of this elementary sheet do not contain hydroxyl groups or active ions, which explains talc’s hydrophobicity and inertness.
Talc is practically insoluble in water and in weak acids and alkalis.
It is neither explosive nor flammable.
Although it has very little chemical reactivity, talc does have a marked affinity for certain organic chemicals, i.e. it is organophilic.
Above 900° C, talc progressively loses its hydroxyl groups and above 1050°C, it re-crystallises into different forms of enstatite (anhydrous magnesium silicate).
Talc’s melting point is 1500°C.
The size of an individual talc platelet (= a few thousand elementary sheets) can vary from approximately 1 micron to over 100 microns depending on the deposit.
It is this individual platelet size that determines a talc’s platyness or lamellarity.
A highly lamellar talc has large individual platelets whereas a microcrystalline talc’s platelets are much smaller.
The elementary sheets are stacked on top of each other, like flaky pastry, and, because the binding forces (known as Van der Waal’s forces) linking one elementary sheet to its neighbours are very weak, the platelets slide apart at the slightest touch, giving talc its characteristic softness.
Talc ores also differ according to the type and proportion of associated minerals present.
They can be divided into two main types of deposits: talc-chlorite and talc-carbonate.
Talc-chlorite ore bodies consist mainly of talc (sometimes 100%) and chlorite, which is hydrated magnesium and aluminium silicate.
Chlorite is lamellar, soft and organophilic like talc.
It is however slightly less water repellent than talc.
Talc-carbonate ore bodies are mainly composed of talc carbonate and traces of chlorite.
Carbonate is typically magnesite (magnesium carbonate) or dolomite (magnesium and calcium carbonate).
Talc-carbonate ores are processed to removed associated minerals and to produce pure talc concentrate.
Talc is a naturally occurring mineral composed of magnesium, hydrogen, oxygen, and silicon which combine to form what’s known as anhydrous (contains no water) magnesium silicate.
Talc is often the main ingredient in loose and pressed face powders, powder foundations, and body powders for adults and children.
Talc is a naturally occurring mineral substance used in a variety of cosmetic and personal care products from baby powders to eye shadows.
Talc is added to absorb moisture, smooth or soften products, prevent caking, and make makeup opaque.
Talc can be mined from the earth or produced industrially.
Some talc is contaminated with asbestos and asbestos fibers, a mineral substance linked to cancer, as a result of its close proximity to talc deposits and mining sites.
Testing talc samples for asbestos is the only way to identify contamination.
Two-thirds of baby powders tested in Korea contained asbestos.
Talc is a naturally-occurring mineral used in some consumer products, including personal care products like cosmetics.
Pure talc and talc-containing rock are mined from the earth.
Talc is made up of magnesium, silicon, oxygen and hydrogen.
Its physical properties make it one of the softest naturally occurring minerals.
There are different grades of talc, with varying degrees of purity (or presence of other minerals).
Talc is milled to different particle sizes, with the finest talc used in cosmetics, pharmaceuticals, and some food products.
The term talc refers both to the pure mineral and a wide variety of soft, talc-containing rocks that are mined and utilized for a variety of applications.
Talc forms mica-like flakes.
Talc is the softest mineral on the Mohs hardness scale at 1 and can be easily cut and crushed.
Talc has perfect cleavage in one direction.
This means that Talc breaks into thin sheets.
As a result, Talc feels greasy to the touch (which is why talc is used as a lubricant).
Talc is a mineral made up mainly of magnesium, silicon, and oxygen.
As a powder, Talc absorbs moisture well and helps cut down on friction, making it useful for keeping skin dry and helping prevent rashes.
Talc is widely used in cosmetic products such as baby powder and adult body and facial powders, as well as in a number of other consumer products.
Talc is a hydrous magnesium silicate with the theoretical formula MgO3Si4O10(OH)2.
Commercial grades of talc often vary considerably from the theoretical purity.
Such products may be a mixture of pure talc mineral and minerals such as dolomite, calcite, quartz, diopside, serpentine, magnetite, pyrite, tremolite-actinolite and mica in different proportions.
Commercial talc is used under various names in the industry.
Talc is used in ceramics, paint making, roofing, insecticide production, rubber and paper industry, cosmetics and pharmacology, asphalt filler, animal feed and fertilizer production.
Depending on the intended use, softness, oil absorption, moisture content, melting point, specific gravity, thermal and electrical conductivity and chemical analysis are important.
Highly prized properties
Talc is a hydrated magnesium silicate.
Talc deposits form from the transformation of high magnesium rocks by siliceous hydrothermal fluids.
Most talc originates from the alteration of dolomite or ultramafic intrusive rocks.
Following this process, talc is always found in combination with other mineral(s).
Carbonates and chlorite are the most common associated minerals.
Each talc deposit has a unique morphology and mineralogy, but all talcs exhibit the following unique properties: softness, water repellency, chemical inertness, platyness, and an affinity for organic substances.
These properties make talc a highly prized multi-functional filler and process enabler in an array of applications from plastics to paper, ceramics to paint.
Talc may crystallize in either monoclinic space group symmetry (C2/c) with two TOT layers (Z = 4) (Gruner, 1934) or triclinic space group symmetry (C-1) (Rayner and Brown, 1973, Perdikatsis and Burzlaff, 1981) with one TOT unit (Z = 2).
Talc is an odorless white to grayish-white very fine crystalline powder (unctuous).
Talc readily adheres to the skin.
Talc is nonflammable, noncombustible, and nontoxic.
Talc is a mineral composed primarily of magnesium, silicon and oxygen.
Talc is a substance often found in cosmetic and personal hygiene products including baby powder, adult body powders and facial powders.
Talc helps absorb moisture, freshen materials, and reduce friction to prevent rashes.
Talc is finely-powdered native hydrous magnesium silicate.
When administered into the pleural space, talc initiates an inflammatory reaction, resulting in adhesion of the visceral pleura to the parietal pleura and fibrosis, thereby effectively closing the pleural space and preventing further accumulation of fluid.
This agent exhibits no intrinsic antineoplastic activity. (NCI04)
Talc is a mineral with formula of Mg3Si4O10(OH)2.
The IMA symbol of Talc is Tlc.
Talc is magnesium silicate hydroxide obtained from a naturally occurring rock ore.
Talc is typically mined in open-pit operations, and cosmetic talcs are mined in Italy, France, Norway, India, Spain, China, Egypt, Japan, and the United States.
Cosmetic talc is typically sterilized by heat treatment.
Talc is known to be used as a bulking agent, opacifying agent, slip modifier amongst its many functionalities.
Talc is a naturally occurring phyllosilicate mineral (hydrated magnesium silicate, Mg₃Si₄O₁₀(OH)₂), known for its extreme softness—ranking 1 on the Mohs hardness scale
Talc typically occurs as foliated or fibrous masses, with a waxy or pearly luster and perfect basal cleavag
Talc is a powdered native, hydrous magnesium silicate sometimes containing a small portion of aluminum silicate.
Talc, common silicate mineral that is distinguished from almost all other minerals by its extreme softness (it has the lowest rating on the Mohs scale of hardness).
Its soapy or greasy feel accounts for the name soapstone given to compact aggregates of talc and other rock-forming minerals.
Dense aggregates of high-purity talc are called steatite.
Since ancient times, soapstones have been employed for carvings, ornaments, and utensils; Assyrian cylinder seals, Egyptian scarabs, and Chinese statuary are notable examples.
Soapstones are resistant to most reagents and to moderate heat; thus, they are especially suitable for sinks and countertops.
Talc is found as a metamorphic mineral in veins, in foliated masses, and in certain rocks.
Talc is often associated with serpentine, tremolite, forsterite, and almost always with carbonates (calcite, dolomite, or magnesite) in the lower metamorphic facies.
Talc also occurs as an alteration product, as from tremolite or forsterite.
One of the remarkable features of talc is its simple, almost constant composition; talc is a basic magnesium silicate, Mg3Si4O10(OH)2.
Unlike other silicates, even closely related ones, talc appears to be unable to accept iron or aluminum into its structure to form chemical-replacement series, even though an iron analog of talc is known, and the structurally related chlorite forms at least a partial series between iron and magnesium end-members.
Talc is distinguishable from pyrophyllite chemically and optically.
Talc, or talcum, is a clay mineral composed of hydrated magnesium silicate, with the chemical formula Mg3Si4O10(OH)2.
Talc in powdered form, often combined with corn starch, is used as baby powder.
Talc is used as a thickening agent and lubricant.
Talc is an ingredient in ceramics, paints, and roofing material.
Talc is a main ingredient in many cosmetics.[6]
Talc occurs as foliated to fibrous masses, and in an exceptionally rare crystal form.
Talc has a perfect basal cleavage and an uneven flat fracture, and it is foliated with a two-dimensional platy form.
The Mohs scale of mineral hardness, based on scratch hardness comparison, defines value 1 as the hardness of talc, the softest mineral.
When scraped on a streak plate, talc produces a white streak, though this indicator is of little importance, because most silicate minerals produce a white streak.
Talc is translucent to opaque, with colors ranging from whitish grey to green with a vitreous and pearly luster.
Talc is not soluble in water, and is slightly soluble in dilute mineral acids.
Soapstone is a metamorphic rock composed predominantly of talc.
USES and APPLICATIONS of TALC:
Talc may also be used in skin care products where it serves as an absorbent.
Talc is also used in some liquid foundations and concealers, where it adds opacity and contributes to the makeup’s texture.
An ongoing concern with talc since the 1970s has been whether it contains asbestos fibers known as chrysotile, which pose a serious risk to lung health when inhaled.
Talc can become contaminated with these fibers during the mining process because asbestos (also a naturally-occurring mineral) is found in nature in close proximity to talc.
This is why the selection of talc mining sites is so important, as is screening all talc batches for the presence of asbestos fibers.
Ground talc is used as an ingredient in ceramics, paper, paint, roofing, plastics, cosmetics, talcum and baby powders, and a variety of other assorted uses such as making rubber and plastics.
Talc is a mineral powder widely used in blushes, foundation powders and even eye shadows.
Talc is also used on the skin as a moisture absorber, hence its use on baby's bottom.
In a cream or balm, Talc also helps reduce the feeling of oiliness.
Talc is also used as an anti-sticking substance and anticaking agent in food products and dispersing agent in animal feed and fertilizers.
Talc-containing feminine hygiene products are widely distributed and commonly used in the United States.
Talc is used as a dusting powder, either alone or with starch or boric acid, for medicinal and toilet preparations.
Talc is also an excipient and filler for pills, tablets, and for dusting tablet molds.
Patents are pending on the use of magnesium silicate as a cement substitute.
Its production requirements are less energy-intensive than ordinary Portland cement (at a heating requirement of around 650 °C for talc compared to 1,500 °C for limestone to produce Portland cement), while it absorbs far more carbon dioxide as it hardens.
This results in a negative carbon footprint overall, as the cement substitute removes 0.6 tonnes of CO2 per tonne used.
This contrasts with a positive carbon footprint of 0.4 tonnes per tonne of conventional cement.
Talc is used in the production of the materials that are widely used in the building interiors such as base content paints in wall coatings.
Other areas that use talc to a great extent are organic agriculture, the food industry, cosmetics, and hygiene products such as baby powder and detergent powder.
Talc is used in many industries, including paper making, plastic, paint and coatings (e.g. for metal casting molds), rubber, food, electric cable, pharmaceuticals, cosmetics, and ceramics.
A coarse grayish-green high-talc rock is soapstone or steatite, used for stoves, sinks, electrical switchboards, etc.
Talc is often used for surfaces of laboratory table tops and electrical switchboards because of its resistance to heat, electricity, and acids.
In finely ground form, talc finds use as a cosmetic (talcum powder), as a lubricant, and as a filler in paper manufacture.
Talc is used to coat the insides of inner tubes and rubber gloves during manufacture to keep the surfaces from sticking.
Talcum powder, with heavy refinement, has been used in baby powder, an astringent powder used to prevent diaper rash (nappy rash).
The small size of the particles makes Talc difficult to keep them out of the air while applying the powder.
Zinc oxide-based ointments are a much safer alternative.
Soapstone (massive talc) is often used as a marker for welding or metalworking.
Talc is also used as food additive or in pharmaceutical products as a glidant.
In medicine, talc is used as a pleurodesis agent to prevent recurrent pleural effusion or pneumothorax.
In the European Union, the additive number of Talc is E553b.
Talc may be used in the processing of white rice as a buffing agent in the polishing stage.
Due to its low shear strength, talc is one of the oldest known solid lubricants.
Also, limited use is made of talc as a friction-reducing additive in lubricating oils.
Talc is widely used in the ceramics industry in both bodies and glazes.
In low-fire art-ware bodies, Talc imparts whiteness and increases thermal expansion to resist crazing.
In stonewares, small percentages of talc are used to flux the body and therefore improve strength and vitrification.
Talc is a source of MgO flux in high-temperature glazes (to control melting temperature).
Talc is also employed as a matting agent in earthenware glazes and can be used to produce magnesia mattes at high temperatures.
Cosmetics & Personal Care: Dusting powders (e.g., baby powder), absorbent and slip agent, filler in makeup products (blush, foundation), skin protectant
Pharmaceuticals: Excipient and tablet/lubricant aid
Industrial: Filler in paper, plastics, paints, varnishes, rubber; pigment; insulation in ceramics and electrical equipment; component of steatite (soapstone) for stoves, switchboards
Other Uses of Talc: Anti-caking agent in food (E553b), clarifying agent for liquids, carrier for agrochemicals, mold lubricant
Talc is also used in lubricants, leather dressings, toilet and dusting powders, and certain marking pencils.
Talc is used as a filler in ceramics, paint, paper, roofing materials, plastic, and rubber; as a carrier in insecticides; and as a mild abrasive in the polishing of cereal grains such as rice and corn.
BENEFITS & CHARACTERISTICS of TALC:
Exceptional softness and lubricity—provides a smooth, silky texture in cosmetics and serves as a talcum powder base
Thermal stability and resistance—effective in heat-insulating and fire-resistant applications
Chemical inertness and non-toxic nature—safe for topical applications when asbestos-free
WHAT IS TALC USED FOR?
Talc is used in several skin care products such as baby powders, face powders, make-up bases, deodorants, foot powder, eye shadows, blushes.
Skin care:
Talc functions as an abrasive, absorbent, anticaking agent, bulking agent, opacifying agent, skin protectant, and slip modifier.
ORIGIN of TALC:
Talc is obtained from naturally occurring rock ore.
Crude talc ore can be sorted (beneficiated) to improve purity of commercial products by either dry or wet processing.
In either case, the talc ore is crushed and ground to a fineness suitable for specific end-uses.
A dilute talc/slurry water is conditioned for flotation by the addition of a frothing agent (often a low molecular weight alcohol), and the slurry is then processed through a series of cells through which air is pumped.
This processing causes bubbles to form, and as the bubbles rise to the surface, the talc particles attach to the bubbles due to their organophilic nature; the non-talc impurities are hydrophilic and do not tend to attach to the bubbles.
The float (or froth) is then collected.
The process is repeated until the desired purity levels are obtained.
The talc particles can be further processed by magnetic separation or acid washing to remove iron-bearing minerals, soluble salts, and metals.
The talc is then filtered, washed, and dried.
WHAT DOES TALC DO IN A FORMULATION?
*ABRASIVE
*ABSORBENT
*ANTICAKING
*BULKING
*OPACIFYING
*SKIN PROTECTING
Talc may be harmful to lungs (difficulty breathing, scarring of the lungs) if one breathes in loose powder products, such as baby powder, body powder, loose face powder.
It may cause ovarian cancer when using products with talc in the genital area.
These products include body wipes, baby powder, body powder, diaper and rash creams, bath bombs or bubble bath products, genital antiperspirants and deodorants.
The final assessment found there are no health concerns from breathing in pressed-powder products, such as pressed powder makeup, dry shampoo or foot powder contact with skin, excluding the female genital area.
Talc is not harmful to the environment.
ALTERNATIVES of TALC:
*SILICA
*ZINC OXIDE
TALC FOUNDS IN
*Baby powder
*Body and shower products
*Lotions
*Feminine hygiene products
*Eyeshadow
*Foundation
*Lipstick
*Deodorants
*Face masks
STERILE TALC:
Sterile talc powder (NDC 63256-200-05) is a sclerosing agent used in the procedure of pleurodesis.
This can be helpful as a cancer treatment to prevent pleural effusions (an abnormal collection of fluid in the space between the lungs and the thoracic wall).
It is inserted into the space via a chest tube, causing it to close up, so fluid cannot collect there.
The product can be sterilized by dry heat, ethylene oxide, or gamma irradiation.
TALC AT A GLANCE:
*A natural mineral composed of magnesium, hydrogen, oxygen and silicon
*Talc serves as an absorbent in skin care
*Requires a specific screening process for safety
FUNCTIONS (INCI) of TALC:
*Abrasive :
Talc removes materials from the surface of the body, helps clean teeth and improves shine.
*Absorbent :
Talc absorbs water (or oil) in dissolved or fine form
*Anticaking :
Talc helps ensure the fluidity of solid particles and limit their agglomeration in powder cosmetic products or hard mass cosmetics.
*Bulking :
Talc reduces apparent cosmetics density.
*Opacifying :
Talc reduces transparency or translucency of cosmetics
*Skin protecting :
Talc helps to avoid the harmful effects of external factors on the skin
*Slip modifier :
Enhance the flow properties of other ingredients.
Slip modifiers do not react chemically with the material(s) to which they are added.
TALC IS PRESENT IN:
Talc is present in 4.61% of cosmetics.
*Talc and powder (80.33%)
*Make-up palette (75.52%)
*Eyebrow palette (71.25%)
*Compact powder (70.52%)
*Bronze powder / sun powder (66.4%)
OCCURRENCE of TALC:
Talc is a common metamorphic mineral in metamorphic belts that contain ultramafic rocks, such as soapstone (a high-talc rock), and within whiteschist and blueschist metamorphic terranes.
Prime examples of whiteschists include the Franciscan Metamorphic Belt of the western United States, the western European Alps, especially in
Italy, certain areas of the Musgrave Block, and some collisional orogens such as the Himalayas, which stretch along Pakistan, India, Nepal, and Bhutan.
Talc carbonate ultramafics are typical of many areas of the Archaean cratons, notably the komatiite belts of the Yilgarn craton in Western Australia.
Talc-carbonate ultramafics are also known from the Lachlan Fold Belt, eastern Australia, from Brazil, the Guiana Shield, and from the ophiolite belts of Turkey, Oman, and the Middle East.
China is the key world talc and steatite-producing country with an output of about 2.2 million tonnes (2016), which accounts for 30% of total global output.
The other major producers of Talc are Brazil (12%), India (11%), the U.S. (9%), France (6%), Finland (4%), Italy, Russia, Canada, and Austria (2%, each).
Notable economic talc occurrences include the Mount Seabrook talc mine, Western Australia, formed upon a polydeformed, layered ultramafic intrusion.
The France-based Luzenac Group is the world's largest supplier of mined talc.
Its largest talc mine at Trimouns near Luzenac in southern France produces 400,000 tonnes of talc per year.
Conflict mineral
Extraction in disputed areas of Nangarhar province, Afghanistan, has led the international monitoring group Global Witness to declare talc a conflict resource, as the profits are used to fund armed confrontation between the Taliban and Islamic State.
ETYMOLOGY of TALC:
The word talc derives from Persian: تالک tālk.
In ancient times, the word was used for various related minerals, including talc, mica, and selenite.
FORMATION of TALC:
Talc dominantly forms from the metamorphism of magnesian minerals such as serpentine, pyroxene, amphibole, and olivine, in the presence of carbon dioxide and water.
This is known as "talc carbonation" or "steatization" and produces a suite of rocks known as talc carbonates.
Talc is primarily formed by hydration and carbonation by this reaction:
serpentine
2 Mg3Si2O5(OH)4+carbon dioxide3 CO2→talcMg3Si4O10(OH)2+magnesite3 MgCO3+water3 H2O
Talc can also be formed via a reaction between dolomite and silica, which is typical of skarnification of dolomites by silica-flooding in contact metamorphic aureoles:
dolomite3 CaMg(CO3)2+silica4 SiO2+waterH2O→talcMg3Si4O10(OH)2+calcite3 CaCO3+carbondioxide3 CO2
Talc can also be formed from magnesium chlorite and quartz in blueschist and eclogite metamorphism by the following metamorphic reaction:
chlorite + quartz → kyanite + talc + water
Talc is also found as a diagenetic mineral in sedimentary rocks where it can form from the transformation of metastable hydrated magnesium-clay precursors such as kerolite, sepiolite, or stevensite that can precipitate from marine and lake water in certain conditions.
In this reaction, the ratio of talc and kyanite depends on aluminium content, with more aluminous rocks favoring production of kyanite.
This is typically associated with high-pressure, low-temperature minerals such as phengite, garnet, and glaucophane within the lower blueschist facies.
Such rocks are typically white, friable, and fibrous, and are known as whiteschist.
Talc is a trioctahedral layered mineral; its structure is similar to pyrophyllite, but with magnesium in the octahedral sites of the composite layers.
The crystal structure of talc is described as TOT, meaning that it is composed of parallel TOT layers weakly bonded to each other by weak van der Waals forces.
The TOT layers in turn consist of two tetrahedral sheets (T) strongly bonded to the two faces of a single trioctahedral sheet (O).
It is the weak bonding between TOT layers that gives talc its perfect basal cleavage and softness.
The tetrahedral sheets consist of silica tetrahedra, which are silicon ions surrounded by four oxygen ions.
The tetrahedra each share three of their four oxygen ions with neighboring tetrahedra to produce a hexagonal sheet.
The remaining oxygen ion (the apical oxygen ion) is available to bond with the trioctahedral sheet.
The trioctahedral sheet has the structure of a sheet of the mineral brucite.
Apical oxygens take the place of some of the hydroxyl ions that would be present in a brucite sheet, bonding the tetrahedral sheets tightly to the trioctahedral sheet.
Tetrahedral sheets have a negative charge, since their bulk composition is Si4O4−10.
The trioctahedral sheet has an equal positive charge, since its bulk composition is Mg3(OH)4+2.
The combined TOT layer thus is electrically neutral.
Because the hexagons in the T and O sheets are slightly different in size, the sheets are slightly distorted when they bond into a TOT layer.
This breaks the hexagonal symmetry and reduces it to monoclinic or triclinic symmetry.
However, the original hexahedral symmetry is discernible in the pseudotrigonal character of talc crystals.
WHAT TYPES OF PRODUCTS MAY CONTAIN TALC?
Talc may be used in products to absorb moisture, prevent caking, improve consistency, or to make a product opaque.
Talc is an ingredient used in personal care products such as loose powders (e.g., talcum powder, baby powder, blush, eyeshadow), and in other forms (e.g., pressed powder, liquid makeup).
Talc is also used in some food items, such as rice and chewing gum, and to manufacture pill tablets.
Talc may also be used during athletic or other activities (e.g. drumming).
Talc is a naturally occurring mineral found in deposits across Canada and in other countries.
Talc has many uses in a range of products.
Talc can be found in:
*self-care products, including:
*cosmetics
*natural health products
*non-prescription drugs
*food as a food additive
*paint
*paper
*putties
*plastics
*ceramics
RELATION TO MINING of TALC:
Open Pit Mining:
Most talc is mined today by conventional open-pit, drill-and-blast, shovel-and-truck techniques.
The major difference from conventional technology is that blasting is minimized to reduce breakage of soft talc ore.
PHYSICAL and CHEMICAL PROPERTIES of TALC:
CAS Number: 14807-96-6
EC Number: 238-877-9
Chemical Formula: H₂Mg₃O₁₂Si₄ (approximation for Mg₃Si₄O₁₀(OH)₂)
Appearance: Odorless white to grayish-white very fine powder (unctuous feel)
Density / Specific Gravity: ~2.5–2.8 g/cm³
Melting / Decomposition: Decomposes > 800–1000 °C; melting ~900–1000 °C
Flammability & Explosive Properties: Nonflammable, non-explosive, not combustible
Solubility: Insoluble or negligible solubility in water
Crystal System & Optical Properties: Monoclinic or triclinic;
refractive indices ~1.538–1.600,
biaxial (–), birefringence ~0.051
Mohs Hardness: 1 (softest known mineral)
INCI / Name: Talc (Talcum Powder)
CAS / EC Number: 14807-96-6 / 238-877-9
Synonyms: Talcum, Soapstone, Steatite, Magnesium Silicate Hydrate
Appearance & Texture: Exceptionally soft white/gray powder, waxy feel
Density: ~2.5–2.8 g/cm³
Melting / Decomposition: ~900–1000 °C; decomposition above 800 °C
Flammability: Non-combustible, nonflammable
Solubility: Insoluble in water
Hardness: 1 (Mohs scale)
Primary Uses: Cosmetics (absorbing/powder), pharmaceuticals, fillers, industrial pigments & insulation
Advantages: Softness, lubricity, thermal/chemical stability, inertness
Color: Light to dark green, brown, white, grey, colorless
Crystal Habit: Foliated to fibrous masses, rare as platey to pyramidal crystals
Cleavage: Perfect on {001} basal cleavage
Fracture: Flat surfaces (not cleavage), fracture in an uneven pattern
Tenacity: Sectile
Mohs Scale Hardness: 1 (defining mineral)
Luster: Waxy or pearly
Streak: White jot to pearl black
Diaphaneity: Translucent
Specific Gravity: 2.58–2.83
Optical Properties: Biaxial (−)
Refractive Index: nα = 1.538 – 1.550, nβ = 1.589 – 1.594, nγ = 1.589 – 1.600
Birefringence: δ = 0.051
Pleochroism: Weak in dark varieties
Ultraviolet Fluorescence: Short UV: orange yellow; long UV: yellow
Category: Phyllosilicate minerals, pyrophyllite-talc group
Formula: Mg3Si4O10(OH)2
IMA Symbol: Tlc
Strunz Classification: 9.EC.05
Crystal System: Monoclinic or triclinic
Crystal Class: Either prismatic (2m) or pinacoidal (1)
Space Group: C2/c or C1
Unit Cell: a = 5.291 Å, b = 9.173 Å, c = 5.290 Å; α = 98.68°, β = 119.90°,
γ = 90.09°; Z = 2 or a = 5.287 Å, b = 9.158 Å, c = 18.95 Å, β = 99.3°; Z = 4
Molecular Weight: 379.27 g/mol
Hydrogen Bond Donor Count: 2
Hydrogen Bond Acceptor Count: 12
Rotatable Bond Count: 0
Exact Mass: 377.8174567 Da
Monoisotopic Mass: 377.8174567 Da
Topological Polar Surface Area: 150 Ų
Heavy Atom Count: 19
Formal Charge: 0
Complexity: 188
Isotope Atom Count: 0
Defined Atom Stereocenter Count: 0
Undefined Atom Stereocenter Count: 0
Defined Bond Stereocenter Count: 0
Undefined Bond Stereocenter Count: 0
Covalently-Bonded Unit Count: 6
Compound Is Canonicalized: Yes
Melting Point: 800°C
Solubility: Practically insoluble in water, in ethanol (96%) and in dilute solutions of acids and alkali hydroxides
FIRST AID MEASURES of TALC:
-Description of first-aid measures
*General advice:
Show this material safety data sheet to the doctor in attendance.
*If inhaled:
After inhalation:
Fresh air.
*In case of skin contact:
Take off immediately all contaminated clothing.
Rinse skin with
water/ shower.
*In case of eye contact:
After eye contact:
Rinse out with plenty of water.
Call in ophthalmologist.
Remove contact lenses.
*If swallowed:
After swallowing:
Immediately make victim drink water (two glasses at most).
Consult a physician.
-Indication of any immediate medical attention and special treatment needed.
No data available
ACCIDENTAL RELEASE MEASURES of TALC:
-Environmental precautions:
Do not let product enter drains.
-Methods and materials for containment and cleaning up:
Cover drains.
Collect, bind, and pump off spills.
Observe possible material restrictions.
Take up dry.
Dispose of properly.
Clean up affected area.
FIRE FIGHTING MEASURES of TALC:
-Extinguishing media:
*Suitable extinguishing media:
Carbon dioxide (CO2)
Foam
Dry powder
*Unsuitable extinguishing media:
For this substance/mixture no limitations of extinguishing agents are given.
-Further information:
Prevent fire extinguishing water from contaminating surface water or the ground water system.
EXPOSURE CONTROLS/PERSONAL PROTECTION of TALC:
-Control parameters:
--Ingredients with workplace control parameters:
-Exposure controls:
--Personal protective equipment:
*Eye/face protection:
Use equipment for eye protection.
Safety glasses
*Body Protection:
protective clothing
*Respiratory protection:
Recommended Filter type: Filter A
-Control of environmental exposure:
Do not let product enter drains.
HANDLING and STORAGE of TALC:
-Conditions for safe storage, including any incompatibilities:
*Storage conditions:
Tightly closed.
Dry.
STABILITY and REACTIVITY of TALC:
-Chemical stability:
The product is chemically stable under standard ambient conditions (room temperature).
-Possibility of hazardous reactions:
No data available
