Perlite
Perlite is a lightweight, porous volcanic glass that expands when heated. It forms from obsidian that has absorbed water over time. Widely used in gardening, it improves soil aeration and drainage, preventing root rot while retaining moisture. In construction, perlite serves as insulation, enhances concrete and plaster, and is used in industrial filtration.
Some theories suggest a connection between perlite and comet impacts, but scientific consensus attributes its formation to volcanic processes.
Shoshone, California, has known perlite deposits in the Black Mountains and Greenwater Range. Mining in the mid-20th century focused on borax and talc, but perlite was also extracted, processed, and expanded for commercial use. Its demand grew due to its usefulness in agriculture, construction, and industry. Perlite is mined, crushed, screened, and heated to create a versatile material for various applications.