Pearl colour is usually defined as consisting of two components:
- the body colour
- the overtone.
Strictly speaking, to this should sometimes be added a third man-made attribute – the dye (or irradiation)!
The dye / irradiation
Let’s deal with this one first.
To begin with, virtually all “black pearls” you see for sale will be dyed. Only pearls from “Pinctada Margaritifera” (the Black Lip Oyster) are naturally black and they’re rare. Rarity, of course, equates to price.
No freshwater pearls are ever naturally black. So, if you see cheap black pearls or freshwater pearls that are black, then you know that their colour is almost certainly artificial.
A complication here arises because not all dying is done for a radical effect. Sometimes it’s done to make the peals whiter, creamier or more golden etc.
Purists would argue that no pearl should ever be dyed and on the whole, the less a pearl has been “tweaked” to make it look better, the higher its value will usually be. However, some buyers are less concerned about that and will happily accept pearls that have had their colour enhanced.
How can you identify an artificially coloured pearl?
Well, most professionals and expert retailers of pearls can usually do so at a glance. Sometimes they’ll also look into any drill holes in a pearl looking for signs of a darker core (a sign of irradiation) or down the length of the hole for major colour variations (a sure sign of dying).
Body colour
Many things can influence the basic body colour of a pearl. The lengthy list includes things such as:
- the type of mollusc;
- the waters it has lived in;
- what materials were used as a nucleus to get the pearl underway in cultured pearls;
- etc.
The basic body colour can vary anywhere from black to near brilliant white with many subtle tones in between such as “gold” “green” and “blue” etc.
This is often the first colour that will strike you when you look at a pearl. It’s something of a matter of opinion but many would argue that pearls are best seen under very soft natural light or equally soft but bright artificial light.
Very strong sunlight can cause the pearl’s colour to be lost in the background illumination. Pearls also really don’t like strong direct sunlight very much and it can be harmful to them, so avoid it if at all possible.
Overtones
These are subtle colours that sometimes seem to “float” as luminescence on the top of the body colour.
These colours can drift and swirl and give rise to expressions such as “white pearl with rose overtones”.
It’s also possible to find pearls that have little or no overtone too.
There is no best or worst here. Much depends upon your personal preferences, style and sometimes just your outfit. Some people have different pearls with different overtones, so that they can better coordinate their outfits.
Prices
All things being equal, black pearls (cultivated) are around 50% rarer than white pearls. As such that means that if all other things are equal, black pearls are typically more expensive.
However, as many black pearls are in fact dyed, the price differences aren’t always very evident. Remember also that many things taken together, give the value of a pearl – and colour is only one of them.