"A" from Orange County:

I didn't care much about my engagement ring, but I did want a diamond. It isn't that I'm superficial or anything, but given the women at my office, if I showed up engaged without a ring I'd have a lot of explaining to do.

Ellen from Oregon writes:

I proudly wear a benitoite wedding ring designed by my husband and me 21 years ago. My husband is a rockhound and, in the months before our wedding, we attended a rock show in western Mass. He saw some faceted benitoite and got all excited. Not only was it unusual to see gem-quality faceted benitoite at a show such as this;  it was cheap. "It's because this is the East Coast and nobody knows what it is!" said my California boyfriend sotto voce.  He turned to fully face me. "How about a benitoite wedding ring?" I beckoned with my hand and said, "Ok, c'mon, sell it." He pointed out that diamonds are vastly overpriced for how truly common they are, that they are mined under questionable conditions both environmentally and labor-wise, and that most of them are mass-produced for jewelry use. I told him I remembered the article I read in the Atlantic years before, in which the efforts of DeBeers to create demand for whatever sorts of diamonds they had in abundance that year was described in jaw-dropping detail.

But benitoite, that was something different, my fiance told me. These benitoite stones were faceted as the result of careful cuts by an individual person who collected the mineral from the one mine in the world it came from, which mine was closed a few years earlier. He showed me how the stone fluoresced in artificial light, turning it from a light sapphire blue to almost purple. And...here he paused for the drumroll in his mind..."it's a titanium mineral." I looked at him quizzically. "That's my chemistry!" said the academic. "I do titanium chemistry!"

"Sold!" I said.

Says another reader:

You're just trying to get out of buying your girlfriend a diamond. Nice try.

I assure the reader that money isn't my concern -- I'd rather light $10,000 afire than buy a $9,000 ring.

If you haven't read it before, I highly recommend this piece from The Atlantic archives, a long look at the diamond industry and its history circa 1982.