Hey Jill!

Nice chip! I see two differences.
1) The chip on the right has in the brass insert the '250 Dollars', 'Hyatt', 'Regency', 'Lake', & 'Tahoe' in each Brass edge marks, while the one on the left has 'Nevada', 'Hyatt', 'Regency', 'Lake', & 'Tahoe' in each Brass edge marks.

2) The metal bars, the one on the right has three bars near the edge mark (one short ~1/2 the length of the other two), while the one on the right has two 'short' bars that are further away from the edge mark...

I too would be interested in finding out more about why the two were made...

NICE FIND!!!

Regards,

Dick