Copper, like silver, has been the victim of a ” corner,” and in 1889 the enormous dealings in copper culmin¬ated in a disastrous debacle, spreading ruin far and “wide,” even to the suspension of banks. Not the least romantic episode in copper as a commercial commodity is the story of the vicissitudes of the Rio Tinto Copper Mine, said to be the largest in the world. This mine, covering eight square miles in extent, was worked by many wealthy people, including the Spanish Govern¬ment, without success, but since its absorption by a large English company it has become one of the best-paying of mining concerns, and produces about one-tenth of the copper in the world. Read the rest of this entry »

Copper itself, however, as an implement of warfare still maintains a conspicuous place as a metal of commerce.
Copper is a brilliant metal of a peculiar red colour. The only other metal anything like it in colour is titanium.
Like other minerals, copper is not only found in large quantities in mines, but its presence has been discovered in all kinds of soils and waters. You can trace it  in seaweed, cheese, meat, eggs, straw and even in man’s liver, kidneys and blood.

The earliest mining of copper appears to have been done by the Egyptians in the Sinai Peninsula, where the tunnels, crucibles and parts of the tools used may , still be seen. They were worked from 5000 B.C. to 1200 3.c. In Europe also they must have been worked at a very early date, as in Spanish copper lodes there have been discovered flint mining implements and skulls of a prehistoric type.
Copper was known and worked by the Greeks and Romans and, alloyed with tin, it became the first metallic compound used by man, under the name of “bronze.” The Romans worked copper in Britain and Spain; and in the latter country the copper mines of the Rio Tinto are still very valuable.

In the New World the copper districts of Lake Superior indicate that primitive man worked there, using stone hammers and hide bags to remove the metal hacked off in lumps. The Aztecs and natives of Peru also used bronze implements in their gold, silver, tin and copper mining, so they had discovered the usefulness of the alloy.

Silver exists in most countries side by side with lead, but the chief mines are in South America, and those of Pachuca in Hidalgo, Mexico, are said to be the first mines in which the Spanish forced slaves to work for them. Near there, is the Real Del Monte, where Peter Terreros, originally a poor muleteer, after a long labour found silver to the value of £3,000,000 sterling, and was rewarded with the title of Count by the Spanish monarch for the loan of £1,000,000, which was never repaid.

Terreros invited his Majesty to the mine, promising him that wherever he should alight from his carriage it should be on a pavement of silver, and that wherever he lodged, it should be lined with the same metal. The King did not go ;   but when Terreros’ own childrenr were baptized the procession is said to have walked on bars of silver.

Equally romantic was the finding of the Comstock Lode,-and the subsequent rush to that spot, the enor¬mous amount of money spent upon development and the colossal failure of the enterprise at the finish. The stories of the Leadville and Silverland Mining Enter¬prises are also fascinating ; but all these belong to the romance of mining rather than of commerce.

Long, however, before the silver of the West was known to Europeans it was being worked in Spain by the Phoenicians, and Diodorus Siculus states that the anchors of ships returning from Spain were of silver. Earlier still is the record that in the days of Abraham silver was being used as a medium of exchange, not coined, but weighed.

A short time ago the Society of Antiquaries announced some interesting discoveries made during excavations at Hengistbury Head, Hampshire. Among the curiosities was a collection of many thousand gold, silver and bronze coins which had once been used by the ancient Britons and the Gauls. Read the rest of this entry »

Numbers of ancient peoples believed amber to be a cure for insanity and fever when worn round the neck as an amulet.
During the reign of Nero the Romans made an ex¬ploration of the amber country, and we are told that 13,000 lbs. of amber were brought to Rome, including a piece weighing 13 lbs. Read the rest of this entry »

Amber is a precious gem which, by reason of its peculiar properties, has helped to play an important part in commerce. Thales, the Greek philosopher, discovered that amber, when rubbed, becomes warm, and attracts light bodies to itself, as the loadstone attracts iron. Thus was founded the science of elec¬tricity, tfXtKrpov (electron) being the Greek word for amber. Read the rest of this entry »

The opal is a non-crystalline mineral of hydrated silica occasionally displaying a beautiful play of colour, hence its value as a gem stone. The precious or “noble” opal, as the real gem is called, is, however, but one variety, and is only found in a few places. Read the rest of this entry »

Besides the Oriental emerald, which, as previously mentioned, is a form of corundum, there is the ordinary emerald found in Peru, Columbia, Bolivia and Siberia. This is a variety of beryl, from which, however, it is distinguished by its colour of emerald green instead of pale green, light blue, yellow or white, the colours of the beryl. This shade of green is produced by the presence of chromium, those of the beryl arising princi¬pally from the presence of iron. The precious emerald is valued, in commerce, next to the ruby and diamond, sometimes before the latter.

The search for emeralds requires great patience and industry, for disappointment is more frequent than success. Often there is little or nothing to guide the prospector, the whole formation of black carbonaceous limestone being covered with earth to a depth of from six to thirty feet, as at Muzo and Cosquez in Columbia, where some beautiful gems are found embedded in. veins of calcite, the veins sometimes being less than six inches in depth.

The earth deposit, frequently covered with jungle, has to be removed before prospecting is possible, and a break may prove quite valueless after months of work have been expended upon it. Emeralds which are exposed in the course of quarry¬ing are carefully loosened and detached from the matrix by a ” pricker,” the other quarried material being broken up by light hammers in sorting sheds. The fragments of these remains are closely examined for gems. Some of the stones found thus can be picked out clean. Others have to be cleansed from the adhering matrix, by treatment with cold dilute hydro¬chloric acid.

Before being marketed, the emeralds are sorted into about fifteen different grades.
Emeralds have been found in different parts of the Andes since the sixteenth century, and the deposits around the district of Muzo, Columbia, previously mentioned, are believed to be inexhaustible, in spite of many disappointments.

The best known and most popular of the corundum gems are ruby and sapphire ; and they are usually found close together.    The ruby is the rarer of the two and therefore more valuable. The price per carat of the sapphire is independent of the size of the gem, but the larger rubies fetch a much higher price per carat than the small ones. Rubies and diamonds are always associated together as the most precious of stones. Thus Dry den sings :

“His ample forehead bore a coronet With sparkling diamonds and with rubies set.”

Palamon and Arcite, iii. 54.

The Gaekwar of Baroda has a coat woven of gold and embroidered with diamonds and rubies which cost £25,000 sterling; the Emir of Scindia possesses a bril¬liant scarlet coat and a cap of black and gold studded with rubies and diamonds costing over £30,000 ; and many other Eastern potentates possess similar collections.

The Oriental ruby, sapphire, emerald; chrysolite, topaz and amethyst are all varieties of corundum, a mineral which is only inferior to the diamond for hard¬ness, and is found in crystalline limestone (e.g. in Burma), and in alluvial sands and gravels derived from igneous and metamorphic rocks.

When coloured, as in the case of all the varieties mentioned above, it shows a striking dichroism, being deeply coloured when viewed along the direction of the vertical axis and pale coloured when viewed at right angles to this direction. Hence the red variety, the Oriental ruby, can be distinguished by this experiment from the garnet, the Balas ruby (found in Bokhara) and the Spinel, which are cheaper, more common and more brittle, and are not corundum gems. Read the rest of this entry »