A beautiful gem of a red color; in its perfect state it is of great value. The ruby is often found perfectly pure and free from all spots or blemishes; but its value is much more frequently lessened by them, especially in the larger stones. It is very hard, being second only to the diamond in this respect; and is often naturally so bright and pure on the surface as to need no polishing; it is often worn in rings, &c., in its rough or native state. The color of rubies varies from the deepest to the palest red, all having more or less of a purplish tinge, which is more plainly perceived in the deeper colored specimens than in the paler ones. Where are Rubies found? They are mostly found in gold mines. We have the true rubies only from the East. The Isle of Ceylon has long been celebrated for these gems; they are found in a river which descends from the mountains; they are brighter and more beautiful than those obtained in other parts, but are very rare. Some crystals are frequently found tinged with the true color of the ruby, but these want its lustre and hardness. Describe the Emerald. It is a precious stone of a beautiful transparent green color, and, when in a state of perfection, nearly equal to the ruby in hardness. The finest and best are found in America, especially among the mountains of Peru; they are also obtained from a few places in the East. These gems are often counterfeited, as are most of the precious stones, there being even false diamonds; the genuine may be known by their extreme hardness and brilliancy. _Counterfeited_, imitated with a view to defraud. _Genuine_, true, real. What is the Turquois? A beautiful blue stone; it is one of the softest of the gems, and some varieties are often used for seals, as they admit of being engraved upon. The turquois is easily imitated, and that often so perfectly as to render it very difficult to distinguish the counterfeit from the true gem. In what countries are they found? The Oriental Turquois comes from Persia, the Indies, and some parts of Turkey; the turquois is also found in various parts of Europe, as Germany, Spain, and France. What is Engraving? The art of cutting metals or precious stones, and representing thereon figures, letters, and devices; the term is, however, more particularly applied to the art of producing figures or designs on metal, &c., for the purpose of being subsequently printed on paper. The ancients are well known to have excelled in engraving on precious stones; many specimens have been preserved, which surpass anything of the kind produced by the moderns. This art is frequently alluded to in the Bible. Engraving on wood, according to some authors, was introduced into Europe from China by Venetian merchants; it is certain the art was practised in eastern and northern Italy as early as the thirteenth century. The invention of copper-plate engraving has been ascribed to a goldsmith of Florence, about the year 1460.