Another store told me really dark sapphires are the best. Is that true?

To answer the question in a very general manner, I say, “no”. This needs some explanation.

While I don’t want to get too technical about describing color, in order to understand gemstones, I have to offer some background. When a person looks at any color they have three things to consider:

  1. The hue. This is whether the item is blue or yellow or another color.
  2. The saturation. This is how deep the shade of the specific color is. It could be a deep blue or a light blue.
  3. The tone of the color. This is whether a color has a blackish undertone or none.

When it comes to gemstones, in very general terms, a color that is highly saturated with a very slight tone or none is usually considered more desirable.

Looking at sapphires, there are many shades of blue. Some are very light colors like the cornflower blues or there are very fine cobalt blues. What makes a blue sapphire attractive is that when you look at it the first thing that should be noticed is that it is blue. If the tone in the background is very black the sapphire may look almost black or a blue so dark it is hard to tell apart from black.

Personally, I like blue sapphires that are as neutral a tone as possible and moderately saturated so that the blue seems to jump out of the gemstone. Very dark, almost blackish blue sapphires can be found for very low prices. I have seen them as low as $2 per carat. These are used in promotional quality jewellery. Very nice blue sapphires that are well saturated can be seen for prices of literally $1000’s of dollars per carat. The range can be amazing.

sapphires

In the picture to the right, I took two sapphires and photographed them against a white background with close to daylight conditions. No touch up has been performed. The slightly smaller sapphire, on the right, is well saturated but has a very black tone and looks almost black. The larger sapphire, on the left, is also well saturated but has a neutral to slightly greyish tone. However, the larger sapphire is far more desirable. The effect on the price is substantial. The smaller sapphire is over one carat in weight and would sell for about $100. The larger sapphire is 1.69 carat in weight and sells for over $3000.

Most often the dark sapphires I have seen are of a lower quality and they are not the best. So if a store starts to tell you otherwise, throw the terms of tone and saturation at them and watch the squirming begin.