- MOHOGANY/GOLDEN SHEEN OBSIDIAN SLAB 150 grams rough/knapping/agate/rock/jasperOpens in a new window or tabBrand New$4.990 bids · Time left16h 3m left (Mon, 03:27 PM)+$8.00 shippingFree returnsTop Rated Plusutahs-goldfever-dealer (17,118) 99.8%