Spinel crystallizes in the isometric system; common crystal forms are octahedra. Spinel is a 7.5-8 on the Mohs scale.This beautiful parcel of amazing hot reddish-pink crystals would be perfect for accent stones or any other project you may be working on. This parcel is a total of 13.06 cts. and is made up 17 pcs. These pictures are not to scale so please read each description for the actual size.