Found this tumbled stone - don't know what it is

[randomsignal]

Hi folks,

I'm a newbie with a little knowledge and a lot of interest in pretty rocks of all kinds. 

I've been collecting them -- mostly from shops and shows -- for decades, but not really organizing them at all. 

Now that I'm retired, I decided to go through my collection and try to identify some of the unlabeled specimens.

I'm hoping you good folks can help me out.

The first one I think I picked up in a random bunch of tumbled stones somewhere out west.

Well, I can't upload an image because "this forum has exceeded its limit" so I'm going to try just describing the stone.

At first I thought it was Obsidian. 

It just looks like a chunk of black glass until backlit with a strong light. 

Then areas of it are a translucent purplish red.

I've never seen anything like it.

Thanks in advance for any help.

[victor1941]

Use google and look at images for obsidian to see if you have a match. Check manmade glass since there is also a lot of it that polishes quite well.