I can't get with "Diamond studded jaw" there's something I read long ago that keeps telling me that there's some else here but damn it if I can put a finger to it but it had to do with his vest. Anyway
here's a bit on a few folks that were rolling in the dough.

In "Our Singing Country" there's a different cowboy version of Diamond Joe. Lomax says "Diamond Joe was a Texas cattleman", the story goes, so rich that he was said to wear diamonds for vest buttons. "I learned this song years ago" says JB Dillingham, for 50 years a conductor on Huston & Texas Central trains running out of Austin. 1935

"Diamond" Jim Brady. His vest buttons also were precious stones, and I think that when remonstrated with for his excessive display of gems, Mr. Brady remarked, "Them as has 'em wears 'em."

Thomas II. Rice
RICE, Thomas II., actor, born in New York city, 20 May, 1808; died there, 19 September, 1860. He was first apprenticed to a wood-carver in his native place, and received his early theatrical training as a supernumerary. Later he became a stock-actor at several western play-houses. About 1832 he began his career in negro minstrelsy at the Pittsburg and Louisville theatres with success, repeating his performances in the eastern cities for several years to crowded houses. In 1836 Rice went to "England, where he made his debut at the Surrey theatre in London. This was followed by prolonged engagements in the British capital and other large cities of the United Kingdom. On 18 June, 1837, he married, in London, Miss Gladstone, and soon afterward returned to his native land. He was for a long time the recipient of a large income, which was squandered in eccentric extravagance. In the days of his prosperity he wore a dress-coat with guineas for buttons, and his vest-buttons were studded with diamonds.

Thanks Q for your post on the "other" Diamond Joe.

Barry