4.9 oz size Hausmannite with quartz - considered rare - Originally named "blattricher Schwarz-Braunstein" in 1813 by Johann Friedrich Ludwig Hausmann, Professor of Mineralogy, University of Gottingen, Germany (February 22, 1782, Hanover, Germany - December 26, 1859, Gottingen, Germany). Renamed by Wilhelm Haidinger in 1827 in honor of Hausmann. ausmannite has a tetragonal distorted spinel structure (due to the Jahn-Teller distortion of the Mn3+-centred polyhedron). When heated above 1473 K, a cubic high-temperature phase appears (Frenzel 1980). This rare find from Arkansas my father found this exploring the area. ** great collector piece CONSIDERED RARE - PRICES USUALLY HIGH - ** ** SEE VIDEO ( IF AVAILABLE ) FOR FULL EFFECTS ** ** WE HAVE MANY BEAUTIFUL MINERALSPECIMENS FROM THE USA AROUND THE GLOBE ** MOST ARE FROM OUR VARIOUS TRIPS ** item # 154 Shipping Fees SHIPPING HANDLING SHIPPING YOUR ITEM SHOULD ARRIVE WITHIN 1-5 BUSINESS DAYS FOR DOMESTIC ORDERS. SHIPMENT IS FIRST CLASS MAIL - UNLESS OTHERWISE STATED. LOOK FOR A SHIPPING CONFIRMATION MAIL. ORDERS WILL BE SHIPPED TO ADDRESS ON FILE. RETURNS: FULL 30 DAY RETURN POLICY ~ BUYER PAYS RETURN SHIPPING ~ CONTACT US FOR ANY CONCERNS. SATISFACATION IS TOP PRIORITY