An English engineer, in the employ of the Mineral Syndicate, told me that in some gold alluvial-deposits brought to him by the aborigines in the interior of Luzon, he had discovered small stones. Subsequent investigations and tests proved them to be rubies and hyacinths. Granted. But I have never heard of precious stones outside of that district; nor do I believe they exist in any quantity there. There is plenty of iron, of excellent quality, in Luzon and in the other islands. There are some deserted mines near Manila that were once worked by the Government; but they have been idle for more than a century. About the year 1750, by promises of great concessions to the State, a Spaniard named Salyado obtained possession of a large iron mine in the district of Mórong. Finding the Indians too indolent to help him, he hired Chinese. He was then attacked by the Church, on the score of employing infidel labor, and eventually he was obliged to send his workmen back to China at his own expense. He was further refused a market for his ore, because, it was said, it was the result of infidel labor. Hence, he found himself ruined. The Government thus adopted a plan to get the valuable mine into its own hands again, after which its interest ceased. Near Angat, early in this century, two Englishmen introduced expensive machinery, and proceeded to mine for iron. They were so cheated by the natives, and received so little in return for the large sums expended, that they simultaneously committed suicide, by blowing out their brains. Peculiar Methods of Mining Copper. Copper is found in many parts of the Philippines, but in very small quantities. In the mountain-ranges in the centre of Luzon, however, deposits have been worked by the natives from a time long before that of the Spaniards. They soften the rocks by wood fires and then make excavations, separating the ore according to quality. Their furnaces are holes lined with clay, and they use blowers of bamboo to produce the necessary draught. The Spaniards recently took hold of the mines, introducing the most expensive machinery and the latest methods; but they failed where the natives had succeeded, and their enterprise collapsed. The Indians still work them on a small scale. The engineers of the syndicate also found a very curious deposit of copper in one of their concessions. This consists of round or pear-shaped nuggets of the metal, with traces of both gold and silver in their composition. Other Minerals and the Coal-fields. The Archipelago is said to be of volcanic formation, and unlimited quantities of sulphur exist on many of the islands. Red lead, silver, and gypsum were also found, and marble, capable of a high polish.