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Spinels. These should be clear, bright, and transparent. Their use is more restricted than tourmalines.
Zircons. White and blue are the most popular, the blue fulfilling the lack of smaller aquamarines of a deeper shade. The demand for brownish and golden colored stones is restricted. White stones should be clear of cloudiness; the blues should reach a deep, brilliant blue to be fine, brownish blue, pale blue, and patchy colored stones being of less value. All look better in artificial light. Avoid stones that are rubbed or flawed. Recutting, except with large specimens, is hardly worth while, but surface polishing often improves a stone.

Topaz. Although an attractive stone, it is not in great demand, and it certainly suffers from the competition of the cheaper citrine. The clear, deep yellows are best, and these are more valuable than the pale blues, whites, and pinks. Depth of body color should be noted, and care should be taken to distinguish stones from yellow fancy diamonds quartz. This is not always easy by visual means. Some South American citrines are very bright and also take a good polish.

Peridots are in fairly general use, although they are not universally popular. They do not reach high prices. Larger sizes are unusual, but small stones often accompany pearls, moonstones, and diamonds in mounted jewelry. The usual color is green, and the pale specimens are of very little value. They are sometimes confused with green tourmalines, which is also the predominating color of this more attractive gem stone. Pink tourmalines are also used, and these may be mistaken for pink topaz. The green variety should not be too dark, and the pink stones should not be too pale. Both should be free of internal lines and flaws. Tourmalines are often of a fair size, and they make good center stones in certain types of jewelry. There are many synthetic spinels and corundums on the market which could be taken for tourmalines at a first glance.

The best garnets are the almandines which have a slightly purplish tinge in the dark red. But they should not be too dark or otherwise they will appear to be almost black. When good specimens are properly cut, they are very attractive and deserve to be used more extensively. They rarely realize more than about $2.80 (so/-) a carat, which is less than most tourmalines. It is difficult to mistake almandine garnets with any other stone, except possibly red spinel.