If you plan on buying your sweetie a diamond ring this Valentine's Day--have we got a deal for you!

Diamonds may be a girl's best friend. But for a first-time buyer like Christian Rosenfield, "I was quite nervous…definitely."

Forget the sticker shock, you need to know the four C’s, color, cut, clarity and carat weight. And if you can figure that out, how do you know you're getting a good deal?

"When I was looking for my wife's engagement ring, the most shocking thing was finding out that the same diamond was selling for different prices at different jewelers," said Ajay Anand.

Anand created the platform, Rare Carat. It's search engine not only compares prices from independent dealers who you can buy from, but its gemologists will tell you if you're getting a good deal on one you saw somewhere else.

"And bring back 50 data points about your diamond. We'll use those data points and our algorithm to predict a price that we think is fair for what that diamond is.”    

Don't want to buy a diamond online? They can also hook you up with one of their "local" partners or you can bring their free report to negotiate with your favorite jeweler.

"We want to make as many sales as possible because it's the consumer for life. It's the relationship."

Alson Jewelers, which has been connecting Clevelanders with diamonds for 80 years, and carries rings from $500 to $1.5 million says, no matter where you buy or how much you spend,the cut is the most important quality.

"You can have two diamonds that are the exact same size, the exact same color, the exact same clarity but if one isn’t cut well, and the proportions aren't outstanding then it will just look dead."

Where he says you can cut corners is on clarity, because no one is walking around with a magnifying glass looking to catch imperfections. Then there's the tossup between color, which is how white the diamond looks. And the carat size, which let's face it is about showing off.

Just remember…"It's something she is going to wear the rest of her life."