jinis
mercon obsidian, mahoni, Sheen obsidian, Snowflake obsidian lan Beludru merak obsidian
basalt alkalin, boninite, basalt alumina dhuwur, agêng segara Pegunungan basalt (morb), basalt tholeiitic, basaltic trachyandesite, mugearite lan shoshonite
fitur
pamblokiran negativity, mbantu kanggo ngreksa marang depresi
tahan struktural dhuwur marang erosi lan iklim, rock grained banget nggoleki