Size is about = 29.8 x 17.9 x 5.3mm
You are looking at a Natural Spiny Oyster Shell cabochon (cab). The total weight is with a thin layer of backing. The penny is shown at 19mm for reference only. It was freeform cut and has a good shine. The stone shown in the picture is the one that you will receive. Thanks for looking and take a look at my other items. I do combine shipping for no extra charge. 
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