Tuesday, August 10, 2010

On Mines and Mining - Part Two

This post includes minerals A-C. My original document, made as it was for personal use, was adorned with many photo references of metals, gems and old alchemical symbols. If any of the text refers to a picture that is not there, just google it and I'm sure you will find a usable reference.

With each material, I give a value in parentheses and then a quick list of its general uses. Art usually refers to jewelry (as in stuff that shows up on treasure lists). Minor, medium and major gems refers to the treasure generation system in Swords and Wizardry and do not give values, since such values are randomly determined. I should also note that in my NOD campaign, I used a measure of 100 coins to the pound, rather than the 10 coins to the pound that appears in games like OSRIC and Swords and Wizardry - adjust values of metal accordingly. The rest is, I'm sure, self explanatory.


Alabaster (6 sp / lb); Art

The alabaster that was used in ancient times was a carbonate of calcium. Alabaster occurs as a deposit on the floors and walls of limestone caves. Alabaster was a common stone used for hardcarving. The Egyptians used it to make perfume bottles, ointment vases and canopic jars. Small vessels used to hold perfume and precious oils were called alabastrons. There is even a record of an entire sarcophagus carved from a block of alabaster. When cut thin, alabaster could be used as a window, a technique used in many Medieval churches.

Amber; Minor Gem

Amber is fossilized tree resin (sap). It has been valued since prehistoric times. Amber is usually yellow-orange-brown, but can range from whitish to pale lemon yellow to brown and almost black. There is even red, green and blue amber, the blue being very rare and highly sought after. Oltu stone is a black amber found in Asia Minor. It is formed from fossilized resin and clay or lignite, and is used to make beads and jewelry. Amber can often be collected after it washes up on sea shores. Amber is supposed to have the power to ward off disease.

Butter of Antimony (300 gp); Poison

Antimony, or stibnum, is a blue-white metal that is very brittle and thus easily crushed or powdered. It is most often found in the mineral stibnite, a soft, grey crystalline substance.

Antimony has a low melting point and is thus easy to cast. It is used to alloy tin, copper or lead.

Alchemists once prepared a substance called butter of antimony, or antimony trichloride. It was so called because of its waxy appearance. Butter of antimony is a soft, colorless solid with a pungent odor. Paracelsus called it Mercury of Life, and used it as a medicine. Unfortunately, butter of antimony is quite poisonous, and all Paracelsus managed to do with it was commit suicide. Butter of antimony was used to make powder of Algaroth, also known as spirits of philosophical vitriol. This was a white powder that was a powerful emetic.

Glass of antimony was also an emetic. It was prepared by putting ground antimony in an earthen crucible over a vigorous fire until it no longer fumed. The remaining substance, called calx, was then vitrified in a wind furnace, creating a transparent, reddish glass.

Antimony was symbolized by the wolf, as it was linked with man’s free spirit or animal nature.

Arsenic (1 gp / lb); Poison, Alloy
Orpiment (2 cp / oz); Pigment, Poison
Realgar (2 cp / oz); Pigment, Poison

Arsenic’s name is derived from the Persian for “yellow orpiment”. It is a metallic grey in color as a metal. Mispickel, realgar and orpiment are the most common arsenic-bearing ores. Mispickel, or arsenopyrite, is a hard, heavy steel grey to silver white mineral. It is found in hydrothermal vents and volcanic areas. Mispickel is also an indicator of gold-bearing ores, especially in reefs.

Realgar, called sandarach by Aristotle, is a soft, orange-red mineral with a sub-metallic luster. The name comes from the Arabic “rahj al-gar”, or “powder of the mine”. In India it was called manseel. Its decayed form, a yellow powder, is called pararealgar.

Orpiment is a yellow to orange mineral found near volcanoes, hydrothermal vents, hot springs and from the decay of realgar. Its name is Latin for “yellow pigment”, and it is also called “King’s Yellow” and hartal.

Dissolved in nitric acid, mispickel produces arsenic fumes and elemental sulfur. As a metal, arsenic was refined from realgar. The realgar was roasted, creating “cloud of arsenic”, or arsenius oxide. This vapor was then reduced to obtain the metal arsenic.

Arsenic’s main use was for murder, especially among nobles. It was called “Poison of Kings” or “King of Poisons” for this reason. The infamous Aqua Tofana was a poison made by a Giulia Tofana in Palermo for 50 years. It was sold both as a cosmetic and as a devotionary object in vials with pictures of St. Nicholas (as “Manna of St. Nicholas of Bari”) to women who wanted to kill their husbands. Aqua Tofana contained arsenic, lead and belladonna, and was colorless and tasteless, and thus easily mixed into drinks.

Arsenic was also alloyed with bronze to make a harder bronze called arsenical bronze. Orpiment and realgar were used as pigments in painting. The Chinese used both as an ingredient in medicines, and the Chinese also incorporated realgar into household ornaments (wine pots, wine cups, and paperweights) to ward off disease. The highly toxic nature of both pigments made them useful as fly poisons and as a poison (Type I) applied to arrows.

Alchemists turned arsenic into a substance they called flowers of antimony, or arsenic trioxide. This substance was obtained by roasting orpiment or realgar. The Chinese used flowers of antimony to treat cancer and other medical conditions, although it is really quite toxic.

Glowstone (2 gp); Equipment, Poison (Weak)

Although not isolated during the Middle Ages, barium was known through the mineral barite. Large deposits of barite in pebble form were found around the city of Bologna, and thus the pebbles were called Bologna stones. Apparently, Bologna stones, if exposed to light, would glow for years, making them attractive to alchemists and witches, and, in a fantasy setting, to dungeon delvers. In a fantasy milieu, they might be called glowstone. Glowstones produce as much light as a candle, but they are quite poisonous.

Aquamarine; Medium Gem
Beryl; Medium Gem, Protection from Evil
Emerald; Major Gem

Beryl is a precious stone named by the Greeks for a blue-green color. It is found in granite called pegmatite and in mica schists. It can be found in a variety of colors including green-yellow, pure yellow and pink. Blue-green beryls are called aquamarines and pure green and pure red beryls are called emeralds and scarlet emeralds. Some emeralds, called trapiche, have a six-pointed grey star pattern. Beryl deposits are also a source of tin (q.v.).

Chalk (8 cp / lb); Equipment

Chalk is a form of limestone composed of calcite. It is formed under deep marine conditions from the accumulation of tiny shelled creatures. Because it is more resistant to weathering than the clays that surround it, chalk often forms tall columns or cliffs. Chalk is white and soft, and thus useful for writing.

Alexandrite; Medium Gem, Divination
Chrysoberyl; Medium Gem, Protection from Possession
Cymophane; Medium Gem

Chrysoberyl is a precious stone that bears no relationship to beryl. It occurs in granite and mica schists, near dolomitic marble and in sands and gravel from river deposits along with corundum (q.v.), garnet (q.v.) and topaz (q.v.). Chrysoberyl is the third hardest gemstone, ranking between corundum and topaz. It develops into twinned crystals in three varieties: ordinary chrysoberyl is yellow-green in color, cymophane is light green with a band of light, and alexandrite is emerald green, red and orange-yellow in coloration.

Smalt (3 gp / lb) Blue pigment

Cobalt is a hard, gray metal named for kobolds. It got the name because early attempts to smelt the metal failed, but managed to produce a toxic arsenic gas. Cobalt is found in a grey mineral called cobaltite. Cobaltite contains cobalt, arsenic, sulfur and iron (10%). It is found with magnetite and sphalerite in metamorphic rocks. Another source of cobalt, and more useful in ancient times, was smaltite. Smaltite is a grey mineral that contains cobalt, iron, nickel and arsenide.

Cobalt, the metal, was not isolated until 1735 by chemist Georg Brandt. The metal was used in ancient times, however, as blue pigment. A mixture of smaltite, quartz and potassium carbonate was roasted, yielding a dark blue glass which was ground into a powder and used as a pigment in glass, ceramics, glazes and paint.

Copper and Malachite
Billon (5 gp / lb); Coins
Bronze (1 gp / lb); Art, Coins, Equipment
Brass (2 gp / lb); Art, Coins
Copper (1 gp / lb); Art, Coins
Hepatizon (2 gp / lb); Art, Equipment
Malachite; Minor Gem
Orichalcum (10 gp / lb); Art
Potin (5 sp / lb); Coins
Speculum (6 sp / lb); Mirrors
Verdigris (3 cp / oz); Pigment (Green)

Malachite is a green stone that is often found with azurite, a blue stone. Malachite occurs in limestone deposits. It is the principal ore containing copper. Copper can also be found in bornite, or peacock copper, and chalcocite, also called copper-glance and vitreous copper. Bornite is a brown to copper red mineral that tarnishes to blue and purple. Chalcopyrite is a brassy to golden yellow color. Bornite occurs in porphyry (q.v.) deposits. Chalcopyrite occurs in granite, diorite and porphyry deposits.

Malachite is valued in its own right as a fancy stone. It is carved into vessels and statuary and is used in green paint.

Copper is a reddish ore that is harder than silver and gold, but softer than iron. Copper can be used to make jewelry and other ornaments. It was once used to make weapons and tools, but was replaced by its many alloys.

Copper is a component in several alloys. Bronze is an alloy of copper and tin (80:20). Bronze is harder than copper, but softer than iron. For thousands of years, bronze was used to make tools, weapon and armor, eventually being replaced in that capacity by iron and later steel. Even after this, it was used to make art objects and coins. Bronze does not corrode easily, making it a useful material for tools and fasteners to be used aboard ships or near the shore. Most copper coins were made from bronze or brass.

Brass is an alloy of copper and zinc (90:10). Brass is harder than copper and softer than bronze. It can be polished to be as shiny as gold, and is thus primarily used as a cheaper alternative to gold in art objects. As mentioned above, many copper coins were really made of brass. Brass has the same value as copper and bronze.

Billon is an alloy of copper and silver, with copper making up more than 50% of the alloy. It was a common material for coins. In a fantasy game, a billon piece (bp) could be placed between a copper piece and silver piece in value. Potin is an alloy that combines copper, lead, tin and zinc. It was primarily used for minting coins. In a fantasy economy, a potin coin could be worth half a copper piece.

Orichalcum was an alloy of copper, gold and silver (50:33:12). By fantasy game standards, orichalcum is worth the same as silver. Hepatizon, or shakudo in Japan, is an alloy of copper, gold and silver (84:8:8). Used in art objects, hepatizon takes on a purple-black patina as it ages. One pound of hepatizon is worth about 20 sp. Speculum was an alloy of bronze and tin (66:33). It is a brittle, white metal that can be polished to a high shine, and is thus used to make superior mirrors.

Copper was also used to produce verdigris. Verdigris was used as a green paint or pigment. It was made by hanging copper plates over hot vinegar in a sealed pot until a green crust formed, or by attaching copper strips to a wooden block with acetic acid and then burying the block in dung. Either process took a few weeks.

The Greeks believed that Demeter’s throne was fashioned from malachite and decorated with gold images of swine and ears of barley. Malachite was believed to provide protection from falling. Copper was associated with Venus.

Coral; Minor Gem

Coral is not a mineral, but rather the skeletons of thousands of tiny aquatic creatures that form a colony. Coral under the sea is alive, but coral that has emerged from the sea is dead. The Greeks believed that coral was seaweed that had been doused by the blood of Medusa as Perseus flew over the sea with her severed head. It usually grows on rocky sea bottoms with low sedimentation and usually in dark environments like the depths or inside caves. Deposits of precious coral can grow at depths of 25 to 800 feet.

Coral can be polished to a glassy shine. It is red to pink in color and is usually cut cabochon or used to make beads. The people of India believed it to be highly magical, and a brisk coral trade developed between the Mediterranean and India. Gauls decorated their arms and armor with it.

Romans would hang coral around the necks of children to ward off danger. They also believed it cured poison from snakes and serpents and diagnosed disease by changing color. Poseidon’s palace is made of coral and gems.

Corundum (Ruby and Sapphire)
Ruby; Major Gem
Sapphire; Major Gem

Corundum is a mineral found in schist, gneiss and some marbles. It is mined from alluvial deposits or underground workings. When it is red, it is called a ruby. All other colors of corundum, blue, brown, green, orange, pink, yellow and colorless, are called sapphires. Some rubies and sapphires have a white, star-shaped inclusion in them, and are thus called star rubies and star sapphires. These stones were highly valued by the ancient Greeks. The rarest stones are called color change sapphires, which show different colors when placed in different lights.

It was believed that rubies brought good luck, and that sapphires aided in understanding problems, boosting magical abilities and killing spiders.

1 comment:

  1. This looks good.

    Speaking as someone who was unaccountably fascinated by the exquisite geological detail in the computer game Dwarf Fortress.


Related Posts Plugin for WordPress, Blogger...