Asbestos is a group of six naturally occurring silicate minerals. The types of asbestos include chrysotile, amosite, crocidolite, anthophyllite, tremolite and actinolite. Asbestos types are categorized into two families: serpentine and amphibole, which indicate their fiber shape.

01. Asbestos Types

What Are the Types of Asbestos?

There are six unique types of asbestos. Each of these types of asbestos occurs naturally. The Environmental Protection Agency (EPA) officially classifies the six asbestiform varieties in the Asbestos Hazard Emergency Response Act (AHERA), which are:

  • Chrysotile
  • Crocidolite
  • Amosite
  • Anthophyllite
  • Tremolite
  • Actinolite

In the past, asbestos was mined across the United States. The last mine, located in California, closed in 2002. However, the United States continues to import tons of asbestos each year. In 2020, the U.S. Geological Survey estimates the United States imported 300 tons of asbestos.

The EPA has various laws in place to regulate the use of asbestos and help prevent exposure. In 1989, the EPA attempted to ban all products that contained this mineral. The ban was overturned and the United States still has not fully banned asbestos. The mineral is currently banned in more than 60 other countries.

Amphibole Asbestos vs. Serpentine Asbestos

The types of asbestos are categorized into two main families: amphibole and serpentine. All types of asbestos are fibrous and composed of hundreds of small silica fibers. The shape of these fibers determines their family.

The serpentine asbestos family is recognized by its wavy or curly appearance, much like a serpent. The fibers are also long and pliable. Serpentine asbestos may also be classified as “sheet silicates” as the fibers form layered sheets. The only member of this family is chrysotile asbestos.

Amphibole asbestos features straight, stiff, needle-like fibers. Some studies suggest these features make amphibole asbestos more dangerous than serpentine asbestos. This is because the fibers are easier to inhale. Asbestos types that fall under the amphibole category include crocidolite, tremolite, anthophyllite, amosite and actinolite.

02. Chrysotile Asbestos

Chrysotile Asbestos

Chrysotile Asbestos Appearance

Chrysotile is the only type of asbestos that falls into the serpentine category. It is sometimes referred to as “white asbestos.” Chrysotile asbestos is made up of long, curly fibers that weave to make sheets.

Chrysotile is the most commonly used type of asbestos in the United States. In previous decades, it was also widely manufactured and used in Canada. This form of asbestos was popular in construction products and automotive parts, such as brake shoes.

Products That Contained Chrysotile Asbestos

  • Cement
  • Asphalt
  • Brake shoes
  • Disk pads
  • Clutches
  • Elevator brakes
  • Roof sealants
  • Textiles
  • Plastics
  • Rubber door seals for furnaces
  • Paper
03. Amosite Asbestos

Amosite Asbestos

Amosite Asbestos Appearance

Amosite asbestos, often referred to as “brown asbestos,” is light brown and straight in appearance. It features thin, needle-like fibers that are easily inhaled when disturbed.

Amosite asbestos has a particularly high level of heat resistance. As a result, this type of asbestos was commonly used in products such as insulation and ceiling tiles. It was the second-most common type in the United States, after chrysotile. Research suggests around 5% of asbestos building materials used in the United States contained amosite asbestos.

Products That Contained Amosite Asbestos

  • Cement
  • Gaskets
  • Chemical insulation
  • Electrical insulation
  • Fireproof products
  • Insulation boards
  • Acoustic insulation
  • Pipe fittings
  • Ceiling tiles
  • Structural steel
04. Crocidolite Asbestos

Crocidolite Asbestos

Crocidolite Asbestos AppearanceCrocidolite asbestos is known as “blue asbestos.” Of the types of asbestos in the amphibole family, it’s known to be the most hazardous. This is because the small size of the crocidolite fibers can make them easier to inhale.

Some studies have shown crocidolite asbestos is responsible for more diseases and deaths than other types.

This mineral features a lower heat resistance than other main types of asbestos. As a result, it was less commonly used. However, it could occasionally be found in some construction materials.

Products That Contained Crocidolite Asbestos

  • Cement
  • Insulation
  • Roof tiles
  • Floor tiles
05. Actinolite Asbestos

Actinolite Asbestos

Actinolite Asbestos AppearanceActinolite asbestos is darker in color than other common types of asbestos. It features long, sharp fibers that may easily be inhaled.

This type of asbestos contains iron, magnesium, calcium and silicon. It’s slightly rarer than other types of asbestos.

As such, this form of asbestos isn’t found as often in consumer products.

Products That Contained Actinolite Asbestos

  • Drywall
  • Cement
  • Insulation
  • Paint
  • Sealant
06. Anthophyllite Asbestos

Anthophyllite Asbestos

Anthophyllite Asbestos AppearanceAnthophyllite asbestos is yellowish-brown in color. This form is composed primarily of magnesium and iron.

Like other types of amphibole asbestos, this type features long, needle-like fibers that are easily inhaled.

Anthophyllite asbestos is rarer than other types of asbestos. As such, anthophyllite asbestos wasn’t often used in consumer products. It has occasionally been found in some cement and insulation.

Products That Contained Anthophyllite Asbestos

  • Insulation
  • Cement
07. Tremolite Asbestos

Tremolite Asbestos

Tremolite Asbestos AppearanceTremolite asbestos can range in color from white to dark green and features long, sharp fibers. This type of asbestos was commonly used in insulation and other construction materials.

Testing of talc and vermiculite has often shown trace amounts of tremolite asbestos. For instance, testing of some talc cosmetic products sold at Claire’s found tremolite asbestos. This sparked concern as these makeup products are marketed to children.

Tremolite asbestos also contaminated the vermiculite mines in Libby, Montana, which led to widespread exposure in the city.

Products That Contained Tremolite Asbestos

  • Plumbing materials
  • Insulation
  • Sealants
  • Paint
  • Roof tiles
08. Dangers of the Asbestos Types

Are All Types of Asbestos Dangerous?

Exposure to any type of asbestos is dangerous. Researchers have found even one-time or minimal exposure to asbestos poses health risks. Exposure to any type of asbestos can cause a number of diseases, including mesothelioma, asbestosis and lung cancer.

Various organizations and health agencies have classified asbestos as carcinogenic, including the EPA and the International Agency for Research on Cancer (IARC).

Individuals who believe they have been exposed to asbestos in the past should speak to their doctor. A health care professional can help monitor for any signs or symptoms of asbestos exposure.

09. Other Minerals

Other Minerals That May Contain Asbestos

Asbestos may be found in other minerals, including talc and vermiculite. In the process of mining these minerals, their proximity to naturally occurring asbestos can result in contamination. This poses a potential health risk to workers and consumers.


Talc is a natural mineral that contains magnesium, silicon, oxygen and hydrogen. It’s used in beauty products, including facial powders, eye shadows, personal care products and baby powder. On its own, talc is considered safe for humans to use.

In recent years, talc has become a concern among health care professionals due to asbestos contamination. Asbestos-contaminated talc has been linked to cases of lung cancer, mesothelioma and ovarian cancer.

There aren’t currently any federal laws that regulate asbestos testing in talc. However, agencies such as the EPA and the Food and Drug Administration (FDA) are working on expanding regulations and enacting rules to protect the health of consumers who use these products.


Vermiculite is a natural mineral that’s commonly used in gardening and insulation. When heat is applied to this mineral, it expands into long, accordion-like strands in a process called exfoliation. The lightweight material can resist chemicals and fire. As a result, vermiculite was a popular additive for soil, filler in animal feed, packing material and construction materials such as insulation and concrete floors.

Just as with talc, vermiculite is safe on its own. However, asbestos contamination has become a major issue with vermiculite.

Between 1925 and 1990, vermiculite was mined near Libby, Montana. This mine accounted for more than 50% of vermiculite production worldwide. However, the mine was contaminated with tremolite asbestos and asbestos-like fibers. Concerns for workers and residents in Libby arose and the EPA became involved with cleanup in the area.

Because the vermiculite mined from Libby was used in home construction, homes with asbestos-contaminated vermiculite insulation likely still stand today.