IT’S LIKE SOME MUTANT OFFSPRING of the DIY Channel and Jewelry Television: Make your own engagement ring. Readers: Would you do this?

UPDATE: Reader Nancy Revy emails:

As someone in the diamond business I have to tell you that I actually think this is pretty cool. Buying a basic diamond for an engagement ring shouldn’t be a intimidating experience. This Amazon page gives the basic client the ability to see what you can get in different cuts and clarity if you hold the price steady. With this information a buyer can go to his local jeweler and see if they can beat the price, given the same criteria for the stone. The key on all of this is the GIA certification, that way you can compare apples to apples, so to speak.

Diamond dealers have a couple of online sources similar to this Amazon page where they can input their criteria, size, color, cut etc. and get a list of available stones that fit their needs. They then make purchasing decisions based on the price versus the price on the weekly RAP sheet. As wholesale dealers we try to buy at 20% off the RAP price and sell to the client at 10% off RAP. A retail store like Tiffany will typically sell a diamond at the RAP price plus 30% percent or more.

For smallish diamonds there is no mystique. They are a commodity and their prices depend on supply and speculation…like other commodities. It’s only when you are working with rare large white and colored diamonds, that the pricing issue becomes murky.

Yesterday at my office I was messing about with a 29 carat diamond. It was so big that I thought it was fake! Someone had to tell me to put down the giant rock!

But Glenn seriously, I know how much you love Amazon, but when you get around to buying the beautiful Dr. Helen a nice little rock for your anniversary, give me a call.

The Insta-Wife isn’t that much into jewelry, but I did buy her some diamond earrings on Valentine’s day. They were not 29 carat, however. Good lord.

Meanwhile, reader Matthias Shapiro writes:

recently purchased an engagement ring and I actually used that very same diamond finder to get an idea of what good diamond prices should be given the cut, clarity and size that I (she) wanted. It was an invaluable tool for establishing some base values so I didn’t get ripped off, which I found was dangerously common. And the lack of sales pressure while I get some understanding of diamonds was really nice.

While I might purchase a diamond that way, I would never use it to select a complete ring, largely because (Amazon techies take note) there is only one view of the ring and it is really hard to get a good perspective on it. Plus theres a lot to be said for seeing it on her hand which is, of course, the ultimate goal.

Yes, this will impose some price discipline even if it never gets a big share of the market. And reader Ananth Sarathy emails:

Recently got engaged, and most people I know and talked to already did something like this, shopping for the stone and then picking a setting. Anyone who makes rings can find the diamond you want based on the certificate number…

Sure everyone knows about color, carat and clarity, but the big secret it looking at the cut angles to get the mathematical idea of how much light will be reflected out (Sorry I am an engineer, so science helps me deal with spending that kind of money on a rock):

http://www.pricescope.com/cutadviser.asp

You plug in the angle information, and it gives a very good idea about the *sparkle* factor of the diamond, which I find, woman are much more concerned about than they originally realize.

Indeed.

ANOTHER UPDATE: Reader Myron Ledford writes: “I did it this past January…I got hooked on Amazon Prime (thanks/curse you) so I decided to look at engagement rings that Amazon had to offer and saw the design your own ring tool. I used it to design a ring for my fiancee that we both love and saved about $200. We did have a problem with the band, it broke about a month after we got it but it needed to be resized anyway. One thing I enjoyed was there was no salesperson to let out slight sighs and tut-tuts as I moved the slider closer to the $100 diamonds than the $125K ones…” Yes, the absence of personal attention can be a minus, or a plus . . . .

MORE: Reader Paxton Helms writes:

Blue Nile has been doing the same thing with diamonds for a whole lot longer than Amazon. I have been 100% satisfied with them. Just a great company and a very smooth diamond purchasing interface. Would hate to see a great site not get mentioned as long as you are talking about Amazon.

And, no, I’m not an employee or PR flack for Blue Nile!!

News to me, but I haven’t been in the engagement-ring interest zone for a while, and hopefully won’t be again.