This is a vintage, men's 10K yellow gold Masonic ring, size 11.5 (falls right between 11.25-11.5 on ring sizer). The center stone is ruby colored. I do not believe it is real Ruby. Marked 10K on inside of band, and total weight is 5.15 grams. 

Some scratches and wear and it looks like a mark on the back on the gold where the ring has been adjusted in the past. See pictures for best details.