1805 Diamond Signet Mourning Ring, Black Enamel, 18K, (sold)
1840s “In Memory Of” Mourning Ring, Black Enamel, 18K, (sold) (in the online shop)

A couple Georgian/early Victorian mourning rings— both probably for men originally. The “in memory of” band is one of the nicest I’ve seen.  A little vertical line separates each letter, making the letters less discernible, and more pattern-like.