Any idea?

[JHoCTX]

First time posting, hoping someone might be able to help out. I found this a long time ago when I was really young so I’m not positive on exact location, but I believe it was on the shores or dam area of Lake Texoma in north Texas. Most likely Grayson and Cooke County. I would find fossils a lot in the rocky areas around the dam. I believe it could be bone. It is textured with small bumps on the part that looks to be bone. Please let me know if you need any more information. 

[ClearLake]

Welcome to the forum!!  I’m not seeing anything that looks like bone internal texture on the broken “ends”.  I think it is more likely interestingly weathered limestone or perhaps some of the burrow traces that are very common in certain sections of the Lake Texoma rocks. Maybe @Mikrogeophagus will have an opinion. 

[Mikrogeophagus]

I really don't know for this one. Those bumps are interesting and a closer/more clear photo might bring some diagnostic info to the table.