None of these diamond fields have been examined systematically by experienced miners with a view to their development, and in fact no definite idea of their limit or their value can be given. But we have the impression that they are far more extensive than has been imagined by mineralogists. The returning gem-seekers who have been educated in the diamond mines of South Africa may investigate ere long these unknown districts and settle the question beyond further inquiry. In California, a few diamonds are reported to have been found here and there among the gold fields, but nothing like a gem placer has yet been revealed. The geological formations of Arizona and New Mexico are more promising than any part of the United States, and explorations may disclose extensive and valuable gem deposits in those regions. The originators of the famous diamond swindle in Arizona chose their locality with more than ordinary sagacity. The account of this daring scheme reads more like romance than reality, and it was more than ordinary boldness that prompted the perpetrators to visit foreign lands, purchase quantities of rough diamonds and then plant them in a distant, desolate, and hostile country to entrap the wary speculator. The success of this piracy was fortunately checked by the sagacity of one of the United States geologists exploring the adjacent territory, who quickly disclosed the fraud, but not in time to prevent the swindlers from pocketing large sums of money from speculators in California. Pliny mentioned Arabia as one of the localities of the gem; but modern investigators believe that he founded his views on the facts of the diamonds being obtained from Arabian merchants, and that they really came from other countries. This probably is the true version of the commerce of the Arabians in those days; but we see no objection to the belief that Arabia may have been a diamond-bearing country in early times, and may possess undeveloped fields at the present day. Northern Africa was also asserted to be diamond yielding, and modern investigators have established the truth of the assertion. In the year 1867 the attention of gem-seekers was turned to vague reports of the discovery of rich diamond fields in South Africa, and the pages of history were examined closely to prove that in ancient times this continent was known as a diamond country. It is undoubtedly true that Africa yielded diamonds to the ancients, for within thirty years several have been found in Algiers, and are now preserved in the collections of Paris. They were discovered in the auriferous sands of the river Goumal, in the Province of Constantine, by natives while washing for gold. They were small in size but of unmistakable character. This discovery strengthens the ancient report of the Carthaginians’ procuring the gems from the Etrurians, who brought them from the interior of Africa.