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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.

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