A Guide to Engagement Rings

By Candice Choi, AP Personal Finance Writer

NEW YORK (AP) — One engagement ring costs $1,000. Another is $10,000. You may wonder why there's an extra zero if you can't tell them apart.

For anyone mulling the big question on Valentine's Day, the cost of the ring can weigh just as heavily as making the commitment. The romance of the affair can make it hard to ask blunt questions about whether you're getting a good deal. But failing to do so could mean paying thousands more than necessary.

The average amount spent on an engagement ring last year was about $3,200, according to The Wedding Report. Several factors can move that price up or down, including the shape of the diamond you pick. Then there are the four Cs — carat, clarity, color and cut, the last of which refers to the stone's overall craftsmanship. You should be able to compromise on one or more areas to save and still get what you want.

You'll also want to consider where to get your diamond, and whether the stone is certified.

So don't buy into the idea that price shouldn't matter when it comes to love. Here's what you should know.

CARAT

First off, don't confuse carat with karat. The latter refers to the purity of gold, while a carat measures a diamond's weight. A one-carat diamond weighs about as much as a paper clip and is smaller in diameter than an eraser on a pencil.

Most diamonds you see are a carat or less, although high-end jewelers carry heftier rocks.

Prices jump substantially with size. So a one-carat diamond won't be merely double the price of a half-carat diamond.

A half-carat engagement ring at Tiffany & Co., for example, costs $3,200. If you move up to a one-carat in the same model, the price nearly triples to $9,200. Go for a two-carat version, and it's $28,200.

So if you can't afford a one-carat ring but fear a half-carat is too small, try playing around with the ring design. A ring with three smaller stones will still cost thousands less than a single one-carat diamond ring.