its not a mineral... its a form of rock.. theres many types of marble and types of obsidian... in the real world, obsidian is usefull as its glass like properties make it good for making arrows or blades, however it can be fragile and is sharp, while marble is heavy, doesnt break easily, but can be easily carved for statues and architecture.

that aside, isnt it a little unfair to have staff run squads? they got rid of that crap on classic. all guilds/gangs/squads are supposed to be equal. no staff members, much less the manager of the server being biased towards one... just causes problems..