51.95g Ureilite Augite-bearing Achondrite Meteorite Slice I NWA 11900

On Offer:  51.95g Ureilite (augite-bearing) full slice of NWA 11900 - Primitive Achondrite Meteorite. Dimensions: 100.39 mm x 76.07 mm x 2.9 mm Official name: NWA 11900 Classification: Ureilite (Augite-bearing)  Description:  A 51.95 gram complete slice, polished on one side, of the augite-bearing Ureilite achondrite meteorite NWA 11900. This ureilite is one of the more rare augite-bearing ureilite classifications. Most ureilite meteorites have a primary composition of a mix of olivine and pigeonite. Pigeonite is a type of pyroxene with a lower Ca (Wo5-25) than augite (Wo24-40). This ureilite has a less common mix of olivine, and two types of pyroxene; pigeonite and augite. This is why it is considered an "augite-bearing" ureilite. The ureilite meteorites are famous for having large equant olivine and pyroxene crystal grains, as well as a relatively large amount of graphite. Occasionally this graphite, which is made of the element carbon is put under such intense pressure (likely