Halloysite-10Å

Occurs in Pinal County.

Chemical Formula: Al₂Si₂O₅(OH)₄·2H₂O

Specific Gravity: 2.2-2.6

Luster: Waxy to earthy

Hardness: 1-2

Halloysite-10Å is a clay mineral that often appears as white, tubular crystals or masses. It is commonly found in weathered volcanic rocks.

Next Pinal County mineral: Halotrichite