This was a fake one sold in Mile High Auctions. So people do get fooled. Notice that top of the slab versus the bottom of the slab. The bottom is clear and normal. The top (and the left side).......not so much.
As a matter of fact, because of the clear picture, if you follow the bottom on along the path, you can see where it turns from looking normal to looking fake (especially if you go from 6 o'clock to 3 o'clock, and 6 o'clock to 9 o'clock).....you can see exactly how he did it and inserted the card into the top of the slab.