Conch Pearls, The Pearl That’s Not Really A Pearl, in the Technical Sense
Conch pearls (pronounced "konk") contain no nacre, so technically they are not actually pearls at all. Instead, the gems are calcareous concretions, similar to kidney stones in humans. They are produced by the Queen conch mollusk (Strombus gigas), which lives primarily in the Caribbean near southern Florida.
Conch Pearls Are A Very Rare Occurrence
No one has yet devised a method for culturing conch pearls, so every one you see will be a natural pearl. Therefore, they are extremely rare and valuable. It is estimated that only one in 10,000 conchs produces a pearl, and that less than 10 percent of those are of gem quality.
Conch Pearls, Small But Pretty In Pink
Conch pearls are usually small in size -- 3 millimeters or less -- and baroque or oval in shape. Their colors are generally pink, yellow, brown, white, or golden. Pink (or a salmon-colored orange-pink) is generally the most sought-after color, while white and brown are relatively rare.
Conch Pearls Have A Flame Structure
In addition to its striking colors, the conch pearl often has another important surface feature called a "flame structure," which is a unique pattern in the coloration. The flame structure generally appears in the pink or white-pink pearls, although the other colors sometimes also exhibit it.
Be Careful, The Color Of Conch Pearls Can Fade
An important fact to remember, if you are considering purchasing a conch pearl, is that its colors tend to fade significantly over time. Experts are not completely sure why, although sunlight is often cited as at least one factor in the fading. Thus, it's recommended that conch pearls be worn primarily in the evening and not exposed to excessive sunlight.
Finding Pairs Of Conch Pearls Is Extremely Rare
Since conch pearls are naturally both rare and unique, finding matching pearls for sets, earrings, strands, etc. is extremely difficult, thus significantly increasing both the cost and the value of such sets.