About the Braganza Diamond: Possibly White Topaz?

Referring to Mawe's statement that the stone may be a white topaz, it is well to remember that the topaz, which consists of a fluo-silicate mixed with silicate of aluminium, is often very apt to be mistaken for the diamond by unpractised eyes. This is especially the case with the colourless stone known as the Goutte d'Eau, and even with the yellow Brazilian variety, which, when skilfully cut, forms a very handsome gem. The German Aulic-councillor, Beireis of Helmstadt, who died in 1809, possessed a stone of this sort, which to the last he believed to be a diamond, although it was said to be as large as an ostrich's egg, and to weight 6,400 carats. He kept it carefully locked up in his cabinet, producing it only on rare occasions, and gave out that he had received it in pledge from the Emperor of China. Nobody, of course, believed this story, but the strange part of it was, that at his death, the stone was found to have mysteriously disappeared. Its existence is vouched for by the testimony of Gothe himself, who was one of the privileged few to whom Beireis showed it. The owner may have possibly, towards the end, discovered his mistake, and destroyed the stone, either for a love of mystery, to which some minds are so prone, or else to save his reputation, by preventing the true character of the gem from becoming known. Some have supposed that this stone was not even a topaz, but merely a piece of rock crystal, like that concerning which Mawe tells the following story:--

"A free negro of Villa do Principe, about 900 miles distant, had the assurance to write a letter to the Prince Regent, announcing that he possessed an amazingly large diamond, which he had received from a deceased friend some years ago, and which he begged he might have the honour to present his royal highness in person. As the magnitude which this poor fellow ascribed to his diamond, was such as to raise imagination to its highest pitch, an order was immediately dispatched to the commander of Villa do Principe, to send him forthwith to Rio de Janeiro, he was accommodated with a conveyance, and escorted by two soldiers. As he passed along the road, all who had heard the report hailed him as already honoured with a cross of the Order of St. Bento, and as sure of being rewarded with the pay of a general of brigade. The soldiers also anticipated great promotion, and all persons envied the fortunate negro. At length, after a journey which occupied about twenty-eight days, he arrived at the capital, and was straightway conveyed to the palace. His happiness was now about to be consummated; in a few moments the hopes which he had for so many years indulged would be realized, and he should be exalted from a low and obscure condition, to a state of affluence and distinction. Such, no doubt, were the thoughts which agitated him during the moments of suspense. At length he was admitted into the presence; he threw himself at the prince's feet, and delivered his wonderful gem. His highness was astonished at its magnitude, a pause ensued, the attendants waited to hear the prince's opinion, and what he said they seconded. A round diamond, nearly a pound in weight filled them all with wonder; some ready calculators reckoned the millions it was worth; others found it difficult to enumerate the sum at which it would be valued; but the general opinion of his highness's servants was, that the treasury was many millions of crowns the richer. The noise which the occurence created among the higher circles may be easily conceived; the general topic of remark and wonder was the negro's offering. It was shewn to the ministers, among whom an apprehension, and even a doubt, was expressed that a substance so large and round might not prove a real diamond. They, however, sent it to the treasury under a guard, and it was lodged in the deposit of the jewel room. On the next day the Conde de Linhares, sent for me, and related all the circumstances which had come to his knowledge respecting the famous jewel, adding in a low tone of voice that he had his doubts about its proving a genuine diamond. His excellency directed me to attend at his office in a few hours, when letters from himself and the other ministers to the treasury should be given me for permission to see this invaluable gem, in order to determine what it really was. Readily accepting a charge of so interesting a nature, I prepared myself, and attended at the hour appointed, when I received the letters, which I presented at the treasury to an officer in waiting. I was led through several apartments, in which much business seemed to be transacting, to the grand chamber, where presided the treasurer, attended by his secretaries. Having my letters in his hand, he entered into some conversation with me relative to the subject. I was then shown through other grand apartments hung with scarlet and gold, and ornamented with figures as large as life representing justice holding the balance. In the inner room, to which we were conducted, there were several strong chests with three locks each, the keys of which were kept by three different officers, who were all required to be present at the opening. One of these chests being unlocked, an elegant little cabinet was taken out, from which the treasurer took the gem, and in great form presented it to me. Its value sunk at the first sight, for before I touched it I was convinced that it was a rounded piece of crystal. It was about an inch and a half in diameter. On examining it, I told the governor it was not a diamond, and to convince him I took a diamond of five or six carats, and with it cut a very deep nick in the stone. This was proof positive. A certificate was accordingly made out, stating that it was an inferior substance, of little or no value, which I signed. . . . The poor negro, who had presented it, was, of course, deeply afflicted by this unwelcome news. Instead of being accompanied home by an escort, he had to find his way thither as he could, and would, no doubt, have to encounter the ridicule and contempt of those, who had of late congratulated him on his good fortune."