Scientific Name: Chiastolite
Group: Silicates - nesosilicates
Chemical composition: Al2OSiO5
Colors: Pink, brown, white, gray, violet, yellow, green, or blue
Hardness: 6.5 to 7.5
Formation: Orthorhombic Crystal; Prismatic form.
Principal Sources: Spain; Brazil; Sri Lanka.
Special Notes: Andalusite is a common regional metamorphic mineral which forms under low pressure and moderate to high temperatures. It is named for the location in Spain where it was discovered. It is a pseudomorph of kyanite and sillimanite.