Pietra dura needs some help

Hi folks, this doesn't seem to fit other forums so posting it here. I have this leather covered box with a pietra dura plaque. Someone in its past life must have used it for a coaster. It has some blemishes; dull, discolored rings and other areas on the 'tile'. Not real noticeable until you start looking closer (which is how I came to purchase it; it was only 99 cents, what could I do?). Is there a safe way to correct these issues (without causing further harm)? The leather is in fair shape, about the same as others I've seen online. Hoping it's not a lost cause...thanks for your suggestions if any!! I know if anyone has an answer it will be found here! I can post more better closeups if you'd like (I was just trying to show the problem areas).

 

On wood furniture they use mayo to get water rings out. I don't know if the stone is porous or not, or if it's coated somehow. It might not hurt to try good old soap and water - just don't get the leather wet or you'll have another problem.

 

Looks like the base material could be marble. Here are some stain removal tips from the Marble Institute,

http://www.marble-institute.com/consumers/stains/

 

Yes, the base is marble and the picture is created from inlaid stones. Thanks for that link, I hadn't found that one. I might give a dry cleaning method a tentative try (0000 steel wool...eeek) on a tiny spot.

 

Ya Brad....thanks for that link.

 

If they're suggesting very fine steel wool, maybe you could try one of those magic erasers first. (I don't know what's used to make them and I've never tried one of them on anything.)

 

I have. Chlorine, I think.

Brad - LOVE your new avatar!

 

Thanks! It is an advertising illustration by J. C Leyendecker. I believe it was for Arrow shirts. I really like his work in general.

 

Very erudite guy!

 

I like the image, too, Brad!

 

Having grown up in a family devoted to the Saturday Evening Post, and in an area in which the Pennsylvania Academy of Fine Arts had been nurturing almost all the fabulous illustrators of the first half of the 20th century, my only problem with the elegant Leyendecker is that he wasn't one of them!

Ah well, I shall make do with Jessie Wilcox Smith, etc., etc., etc.