Weight/Size: 10.25oz, 4×3.8×1.2 inches. Honey colored calcite crystals in Mercenaria Permagna (fossilized clam shells)in gray sparry limestone matrix. Found in Rucks Pit, near Ft. Drum, Okeechobee County, Florida. The Calcite Replacing Mercenaria Permagna, fluoresces brilliantly greenish yellow in both long and short wave ultraviolet light. The Calcite’s golden color is due to iron atom in the forming process of Rucks Pit. The clam shell geode’s (as some people came them)are found in the Nashua Formation. The age of these Mercenaria fossils is late Pliocene to early Pleistocene (1 – 1.5 million years old).