In New Magincia there is a vendor stall (vendor named ATM), it is on the east side of the fountain area in middle of town... he keeps a nice supply of granite of all types...the menu is hard to get use to at first... but scan thru his wares.. the buy options is on the left side of menu.. click arrow beside what you want to buy ... enter amount at bottom... click trade, it will ask you to confirm amount and cost... click ok..