“Yes; but I want you all to bear it in mind, for it will explain a discovery I have made.  Before I get to that, however, I want to say that at one time the island of Ceylon supplied the world with its most famous pearls.  The early Egyptians discovered them there, as well as on the Persian and Indian coasts.  The pearl which Cleopatra is said to have dissolved in wine and swallowed was worth about four hundred thousand dollars in our money; but of course pearls were scarce in her day.  A single pearl was cut in two and used for earrings for the statue of Venus in the Pantheon at Rome, and the sum paid for it was equal to about a quarter of a million dollars.  Sir Thomas Gresham, in the days of Queen Elizabeth, had a pearl valued at about seventy-five thousand dollars which he treated in the same manner Cleopatra did, dissolving it in wine and boasting he had given the most expensive dinner ever known.”

“All of which—­” began Maud, impatiently.

“All of which, Miss Stanton, goes to show that pearls have been of great price since the beginning of history.  Nowadays we get just as valuable pearls from the South Seas, and even from Panama, St. Margarita and the Caromandel Coast, as ever came from Ceylon.  But only those of rare size, shape or color are now valued at high prices.  For instance, a string of matched pearls such as that owned by Princess Lemoine is estimated as worth only eighty thousand dollars, because it could be quite easily duplicated.  The collection of Countess Ahmberg was noted for its variety of shapes and colors more than for its large or costly pearls; and that leads to my great discovery.”

“Thank heaven,” said Flo, with a sigh.

“I have discovered that our famous expert.  Le Drieux, is an arrant humbug.”

“We had suspected that,” remarked Maud.

“Now we know it,” declared Colby.  “Pearls, I have learned, change their color, their degree of luster, even their weight, according to atmospheric conditions and location.  A ten-penny-weight pearl in Vienna might weigh eight or nine pennyweights here in California, or it is more likely to weigh twelve.  The things absorb certain moistures and chemicals from the air and sun, and shed those absorptions when kept in darkness or from the fresh air.  Pearls die, so to speak; but are often restored to life by immersions in sea-water, their native element.  As for color:  the pink and blue pearls often grow white, at times, especially if kept long in darkness, but sun-baths restore their former tints.  In the same way a white pearl, if placed near the fumes of ammonia, changes to a pinkish hue, while certain combinations of chemicals render them black, or ‘smoked.’  A clever man could steal a pink pearl, bleach it white, and sell it to its former owner without its being recognized.  Therefore, when our expert, Le Drieux, attempts to show that the pearls found in Jones’ possession are identical with those stolen from the Austrian lady, he fails to allow for climatic or other changes and cannot be accurate enough to convince anyone who knows the versatile characteristics of these gems.”