Unsure of Wood Type? [pic]

Please forgive me if this is posted in the incorrect topic section-I wasn't sure where else to put this.

I have a chest of drawers made of a very heavy, very dense wood. My father-in-law carved a stump of this same wood that he found on the side of the road [read: someone's trash] in Baton Rouge, La.

While he was cutting it, he said the wood was so difficult to work with that the stump dulled his chainsaw. It was also so dense, he said, that the chainsaw even bounced or skidded a little.

Untreated, the colors in the grain range from a dark beige to deep brown. These photos show varnish or a sealant on the wood, so the colors are light gold to nearly black in the darkest spots.

Neither he nor I have any clue what type of wood this is, but I suspected it to be pecan or grafted walnut [though I'm not entirely sure what "grafted" means].

Does the grain or description look familiar to anyone? Thank you so much.

http://picasaweb.google.com/lh/photo/5ryNrOipEDgIc2yAtU7MsQ?feat=directlink
http://picasaweb.google.com/lh/photo/xO9JfQ6MeWFY4_ZJffWZhA?feat=directlink