For many of us, buying diamond engagement rings are the third most expensive purchases we make, after a home and a car. But they are also very risky, since not everyone who is on the lookout for a good engagement ring is conversant about choosing a good one. This makes people like us vulnerable to dishonest people out to cheat you by selling a poor grade diamond at an exorbitant price.

To avoid such pitfalls, do the following:

Read all you can about diamonds: Research the subject of diamond buying and be as knowledgeable about it as you can. After all, knowledge is power.

Buy only from reputed jewelry stores: You may decide to buy online or at a jewelry store—in either case, ensure you know all there is to the store in question. Go to the store and quiz the salesman about diamonds to understand his level of knowledge on the subject.

Always ask for a certificate: Never buy a diamond without asking for a certificate or you could easily be duped. But having a certificate isn’t everything—you need to read the fine print written in the certificate to understand what it certifies you for, and how each factor covered therein influences the price and quality of your ring.

The “4Cs” of diamonds: Understand all there is to the 4Cs of diamond buying—cut, clarity, carat and color. This is something few people are informed about, and therefore cannot understand how they influence the price and quality of a diamond.

Lastly, treat the diamond you buy as a big financial buy. This means you set a budget before you buy a diamond and don’t exceed it. And, if you remain objective while buying, you are sure to buy a good diamond at a good price.