Astrophyllite is a rare titanium mineral found in some unusual granites and syenites.
It produces a variable luster that can be nearly metallic in one specimen to vitreous in another.
Its name translated means star sheets and probably is in allusion to the intergrown starlike aggregates that it can form.
Color is usually golden yellow or yellowish brown, but also greenish brown specimens are found.
Luster is vitreous or submetallic to metallic, can be pearly on cleavage surfaces.
Transparency: crystals are translucent to opaque.
Crystal System is triclinic; bar 1
Crystal Habits include small tabular or bladed crystals often grouped in starlike aggregates.
Also found in lamellar massives.