Talc Rock
Most people are familiar with the mineral known as “talc”. It can be crushed into a white powder that is widely known as “talcum powder.” This powder has the ability to absorb moisture, absorb oils, absorb odor, serve as a lubricant, and produce an astringent effect on human skin. These properties have made talcum powder an important ingredient in many baby powders, foot powders, first aid powders, and a variety of cosmetics.
A form of talc known as “soapstone” is also widely known. This soft rock is easily carved and has been used to make ornamental and practical objects for thousands of years. It has been used to make sculptures, bowls, countertops, sinks, hearths, pipe bowls, and many other objects.
Although talcum powder and soapstone are two of the more visible uses of talc, they account for a very small fraction of talc consumption. Its hidden uses are far more common. Talc’s unique properties make it an important ingredient for making ceramics, paint, paper, roofing materials, plastics, rubber, insecticides, and many other products.
Talc is a hydrous magnesium silicate mineral with a chemical composition of Mg3Si4O10(OH)2. It is usually green, white, gray, brown, or colorless. It is a translucent mineral with a pearly luster. It is the softest known mineral and is assigned a hardness of 1 on the Mohs Hardness scale. It’s greasy to soapy feel and its value as a high-temperature lubricant.
Occurrence:
In talc-rich schists or steatite through hydrothermal alteration of mafic rocks (steatitization) subsequent to serpentinization during greenschist facies metamorphism. Also formed by thermal low-temperature metamorphism of siliceous dolostones.
Association:
Actinolite, tremolite, chlorite, pyroxene, vermiculite, serpentine, anthophyllite, dolomite, and calcite.
Uses of Talc
Talc is used as a filler, coating, pigment, dusting agent, and extender in plastics, ceramics, paint, paper, cosmetics, roofing, rubber, and many other products.
- Plastics
It is mainly used as a filler. The platy shape of talc particles can increase the stiffness of products such as polypropylene, vinyl, polyethylene, nylon, and polyester. It can also increase the heat resistance of these products and reduce shrinkage. Where the plastic is extruded in the manufacturing process, talc’s very low hardness produces less abrasion on equipment than harder mineral fillers.
- Ceramics
in the manufacturing of ceramics products such as bathroom fixtures, ceramic tile, pottery, and dinnerware. When used as a filler in ceramics, talc can improve the firing characteristics of the greenware and the strength of the finished product.
- Paint
Most paints are suspensions of mineral particles in a liquid. The liquid portion of the paint facilitates application, but after the liquid evaporates, the mineral particles remain on the wall. Talc is used as an extender and filler in paints. The platy shape of talc particles improves the suspension of solids in the can and helps the liquid paint adhere to a wall without sagging.
Powdered talc is a very bright white color. This makes talc an excellent filler in paint because it simultaneously serves to whiten and brighten the paint. Talc’s low hardness is valued because it causes less abrasion damage on spray nozzles and other equipment when paint is applied.
- Paper
Most papers are made from a pulp of organic fibers. This pulp is made from wood, rags, and other organic materials. Finely ground mineral matter is added to the pulp to serve as a filler. When the pulp is rolled into thin sheets, the mineral matter fills spaces between the pulp fibers, resulting in a paper with a much smoother writing surface. Talc as a mineral filler can improve the opacity, brightness, and whiteness of the paper. Talc also can also improve the paper’s ability to absorb ink.
- Cosmetics and Antiperspirants
Finely ground talc is used as the powder base of many cosmetic products. The tiny platelets of a talc powder readily adhere to the skin but can be washed off easily. Talc’s softness allows it to be applied and removed without causing skin abrasion.
Talc also has the ability to absorb oils and perspiration produced by human skin. The ability of talc to absorb moisture, absorb odor, adhere to the skin, serve as a lubricant, and produce an astringent effect in contact with human skin make it an important ingredient in many antiperspirants..
- Roofing Materials
Talc is added to the asphaltic materials used to make roofing materials to improve their weather resistance. It is also dusted onto the surface of roll roofing and shingles to prevent sticking.
- Dimension Stone
A rock is known as “soapstone” is a massive variety of talc with varying amounts of other minerals such as micas, chlorite, amphiboles, and pyroxenes. It is a soft rock that is easy to work, and that has caused it to be used in a wide variety of dimension stone and sculpture applications. It is used for countertops, electrical panels, hearthstones, figurines, statuary, and many other projects.
- Other Uses of Talc
Ground talc is used as a lubricant in applications where high temperatures are involved. It is able to survive at temperatures where oil-based lubricants would be destroyed.
Talc powder is used as a carrier for insecticides and fungicides. It can easily be blown through a nozzle and readily sticks to the leaves and stems of plants. Its softness reduces wear on application equipment.
The global talc industry and marketing
The future of the talc market looks promising with opportunities in plastic, paper, and paint & coating applications. The global talc market is expected to reach an estimated $1.7 billion by 2021 and is forecast to grow at a CAGR of 3.0% from 2016 to 2021.
World talc demand is forecast to increase over the next five years by 2.3%py. Growth will be led by the plastics industry, with demand also increasing in coatings, food processing, and technical ceramics markets. These areas of growth will more than offset the decline in demand seen in the paper sector.
Talc is used in polypropylene, the use of which is growing in automotive vehicles in order to reduce vehicle weight. This is a double bonus for talc, as its intensity of use is also rising as talc imparts the mechanical properties needed to meet light-weighting requirements such as strength and stiffness.
Leading talc producers are focusing on the production of specialtymicronized grades for use in plastics compounding, reflecting the changing patterns of demand. IMERYS Talc’s expansion at Timmins in Canada in 2014/15 represents the first regional production of high-brightness, high-lamellar micronized talc, replacing imports traditionally from China and more recently, primarily from Pakistan.
The largest end-use for talc has traditionally been in the paper sector, and in 2013 it still was. However, Asian papermakers are following trends seen in industrialized countries and talc faces substitution from granular and precipitated calcium carbonate in filling and coating markets. One bright spot is that demand for talc is growing in pitch control, as paper recycling rates improve. By 2019, plastics will have overtaken paper as the largest consuming sector for talc worldwide.
Main Countries Producing Talc
2018 Mine Production of Talc
The values above are estimates of mine productions in thousands of metric tons from the USGS Mineral Commodity Summaries.
