پنبه کوهی یا پنبه نسوز یا آزبست (به انگلیسی: Asbestos) نام گروهی از ترکیب‌های معدنی منیزیوم و سیلیسیوم است که بیشتر در طبیعت به صورت الیاف معدنی و سنگ یافت می‌شود. این مواد به خاطر مقاومت زیادی که در برابر گرما و آتش دارند به عنوان مواد نسوز بکار می‌روند. گاهی به این ماده «پشم شیشه» نیز گفته می‌شود. در ساختمان پنبه کوهی یا پنبه نسوز، عناصری مانند سیلیس، منیزیوم و آهن وجود دارد. پنبهٔ کوهی در طبیعت به رنگ‌های سفید، قهوه‌ای و آبی به چشم می‌خورد. این ماده سرطان زا و استفاده آن در اروپا و آمریکا ممنوع است. پنبهٔ نسوز نمونهٔ خوبی است از ماده‌ای که مولکول‌های غول‌پیکر یک‌بعدی را تشکیل می‌دهد. مولکول‌های غول‌پیکر پنبهٔ نسوز زنجیرهٔ درازی است از اتم‌ها، که ساختمان ریشه‌گون یک کانی نیز از همان ناشی می‌شود. این مولکول‌ها پهلو به پهلوی هم جای گرفته‌اند. بستگی آنها به یکدیگر با نیروهای ضعیف کششی است
The Six Asbestos Types Although there are actually over 100 minerals that have asbestos-like properties, the US government has only officially recognized six. These six types of asbestos are:.
Chrysotile asbestos. The fibers that compose most forms of asbestos have small, straight, and sharp shapes, often described as “needle-like.” Chrysotile asbestos (or “white asbestos”) is the exception to this rule; its fibers actually have curly spiral-like shapes. This shape makes them less like to be inhaled, and thus less likely to cause health problems. Chrysotile asbestos is viewed as relatively safe and is still used in some capacities in the US; however, long-term exposure can create major health problems
Chrysotile asbestos.
Amosite asbestos . Amosite asbestos fibers are straight and usually gray or brown, earning amosite the nickname “brown asbestos.” After Chrysotile asbestos, brown asbestos used to be the second most common type of asbestos used in commercial products. Commercial use of this substance has decreased greatly since its dangers were proven in recent decades. Several countries have banned brown asbestos outright; in the US, its use is strictly regulated.
Amosite asbestos
Crocidolite asbestos. Also known as “blue asbestos,” crocidolite asbestos is composed of very fine and very sharp fibers. Compared to other forms of asbestos fibers, crocidolite’s are easily broken and very easily inhaled. Fortunately, blue asbestos was the least commonly used type in the US, due to its being weaker and less flame-resistant than other types. It is the most dangerous type of asbestos
Crocidolite asbestos.
Tremolite asbestos. Tremolite asbestos naturally forms in large masses in many parts of the world, including Canada and certain parts of the US. While it was never among the most commonly used forms of asbestos, it is among the most dangerous. Tremolite has been found in several different household products, including talcum powder and even children’s toys
Tremolite asbestos
Anthophyllite asbestos. Anthophyllite asbestos is not as durable as other forms, meaning it did not have as many industrial uses in the US. However, it has been used as a component in certain products such as paint and sealants. Miners, painters, and shipyard workers are especially vulnerable to anthophyllite-related diseases
Anthophyllite asbestos
Actinolite asbestos. Actinolite asbestos is similar to tremolite: both range in color from white to green, both are formed in certain kinds of rocks, and neither has a long history of industrial use. Actinolite comes in two forms: one that is composed of long, thin fibers and one that is not. Fibrous actinolite is highly dangerous, as are all forms of asbestos. Non-fibrous actinolite, however, does not carry the same risk
Actinolite asbestos.