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The upheaval in 1914 also led to a depressed market, but with the trade boom that followed, prices began to rise until, in the early 1920s, new high levels were reached. World financial depression followed once more, and the recovery that set in was gradual until restrictions in trading and loss of confidence in paper currencies led to a considerable demand for all precious stones, particularly the fine and large specimens.

The prosperity of the U.S.A. had a good effect on the world’s market. This vast country bought a considerable proportion of the world’s finest stones, especially diamonds, and as the large population was able to consume a huge quantity of all kinds of stones, the general effect was to higher prices. This was so despite the fact that former consumers, such as Russia, Austria, and Italy were almost out of the market.

Red, as a color, has not been really fashionable for some years. Mining for rubies has also been rather spasmodic and generally unsuccessful. So an increase in the demand for rubies has found a scarcity of rough material, which still remains. On the other hand, sapphires do not realize the high prices of rubies, but there is always a good demand for them and their values have now reached a very high level. They are probably the most popular of the precious colored stones, blue being a favorite color in many countries.
Although the supply of gem diamonds is controlled, these stones would, in any event, have a high value owing to their many uses in modern industry. Their price is maintained according to world demand, working costs, and profits, and since 1940, values have risen enormously. There is no “normal” price level to which one may refer, but since 1936, fine large cut brilliants have appreciated considerably in price. In 1954, fine quality diamonds of one carat were realizing up to about $504 (£180) in the trade. Anything over one carat and up to two carats was worth up to $560 (£200) a carat, these prices being for modern cut, first quality stones. It must be emphasized that such stones must be loupe clean and blue white or fine white, modern cut, and well proportioned, to obtain such prices. And this refers to unmounted stones, so the price for a complete new article of jewelry which incorporates diamonds is still further increased in Britain and the United States by the purchase or sales tax.