What is meant by Ochreous?
Consisting of ochre, a kind of earth with a rough and dusty surface, composed of fine, soft, clayey particles, which readily separate in water. There are various colored ochres, as red, yellow, blue, green, &c.; they are very useful in many of the arts.
What term is used to denote the quality of the Diamond?
In speaking of the value of diamonds, we distinguish them as "diamonds of the first water," meaning those which possess the greatest perfection and purity, which ought to be that of the clearest drop of water: when they fall short of this perfection, they are said to be "of the second or third water," and so on till the stone may be properly called a colored one.
What is the Ruby?
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.