Well it's a neat rock but I don't see any writing on it. Could you maybe put some paper over it and make a rubbing of the writing? That might help a bit.

Looks to have been shaped by human hands at some point in time.

Going to hazard a guess as Central American, taken by a Spanish conquistador at some point and lost at sea. Considering the flat nature of the item the currents could have brought it from anywhere around the Caribbean Sea. At least I would guess at that before I went to the Atlantean possibility.

What is it, who knows probably decorative based on your observations of a shiny stone or whatnot.

Can you place it directly on your scanner and scan both sides of it? Sometimes using a photo editing program you can play around with the shading and see things better. Just a thought.

I wish I hadn't dropped it because it had a whole different feal to it with the small crystal like stud in it. It was perfectly centered in the back towards the fatter side. You can see the chip, well maybe you can, in the back picture.

As mentioned, the rim around it is peculiar.

I used to make jewelry with slices of deer anter, that had a rim similar. Instead of being a rock, maybe it's deer antler that has been in the water a while?

If you think one of the images is a horse, that would mean it is probably after the Spanish came then. A skull above it could symbolize the death the Spanish brought with them--both from disease and outright killing.
The Taino were an indigenous group in the Caribbean that were basically wiped out by the Spanish by the above ways....
I obviously don't know--just throwing out ideas.

edit: After looking at your sketch, the anchor really stood out. And is that an "M" and a "U"? Weird.

[edit on 29/7/2010 by Chamberf=6]

My first thought is that it might be a "Piece of Eight" - a coin from the sunken Spanish ships in that area. I had quiet a few of them from diving in Key West. It may be worn down by the water making it difficult to read. I also use to find some interesting chards of pottery from the ships, a lot of them were marked. Its always a thrill to find something interesting such as you have.

Forgot to leave this for you

Spanish dollar
From Wikipedia, the free encyclopedia


The Spanish dollar (also known as the piece of eight, the real de a ocho or the eight-real coin) is a silver coin, worth eight reales, that was minted in the Spanish Empire after a Spanish currency reform in 1497. Its purpose was to correspond to the German thaler. It was the coin upon which the US dollar was based, and it remained legal tender in the United States until the Coinage Act of 1857 discontinued the practice. Because it was widely used in Europe, the Americas, and the Far East, it became the first world currency by the late 18th century. Many existing currencies, such as the Canadian dollar, United States dollar, and the Chinese yuan, as well as currencies in Latin America and the Philippine peso, were initially based on the Spanish dollar and other 8-reales coins

Looks to me like an old amulet.

It is man made, perfectly formed shape and uniform in thickness, etc. I would like to see a close up of all facets to see what the OP sees on it.

Sitting in salt water for however long wouls have caused some build up on the surfaces.. so maybe it can be cleaned to reveal what is on it?