In his past talks about quartz and its relatives, Si Fraser mentioned some of the characteristics of our old friend silicon dioxide.
Besides its usual list of physical traits, a hardness of 7, specific gravity of 2.65, refractive index of 2.54, transparent to opaque color, with agate, especially appearing in nearly any color, conchoidal fracture, hexagonal or trigonal crystal form, bull's eye interference figure, etc. quartz has certain other attributes. It is very stable chemically and physically, and appears as crystals, microcrystalline form and amorphous forms. These forms are practically insoluble in acids, but are soluble in certain alkaline solutions. Quartz does not readily oxidize because its composition already has all the oxygen it needs, so it does not readily weather. It has an extremely high melting point 1600 degrees C. And is composed of two very plentiful elements silicon and oxygen, combined in very simple ways.
No wonder it is so plentiful on the earth's surface, and with so many good features going for it is the beauty queen of the lapidary's eye. What would lapidaries and carvers do without it?
Is it a Nodule, Geode or Concretion?
A Nodule is a rounded mass of irregular shape, a little knob or lump of any kind of mineral. The word nodule comes from the Latin word, meaning "knot."
A Geode is a nodule which is hollow or has a cavity that may be lined with one or more minerals. The word geode comes from the Greek, meaning "Earth form."
A Concretion is a mass formed by the aggregation and precipitation of some mineral such as quartz or calcite, around a nucleus which is often a fossil or small pebble. The word concretion comes from the Latin, meaning "to grow together."
Beads and Wampum
Native American beads were made of various materials such as shell, bone, pearls, metals, porcupine quills, gumwood, pottery, teeth and seeds. When they were made of metal they were usually gold, silver or copper. Many trade beads are found with other Indian artifacts
Columbus was probably the first to bring trade beads, when he gave beads to the Indians to win their friendship. The shell bead is the most common in America and was made in many shapes such as disc, tube shaped, barrel-shaped and spherical. The shell was considered sacred by many tribes as it came out of the water. Beads were decorated in various ways, such as by carving, painting, inlaid work and even by putting skins over a portion of the bead, the more the value placed on it.
Where did the bead originate? No general answer has been obtained but beads have been found with all primitive peoples.
When beads were used as a medium of exchange, they were called wampum. The majority of wampum was made of shell in a cylindrical shape, about 1/4 inch long and were used interchangeably as adornment or as a medium of exchange.
The Feel of Jade
A young Chinese, who wanted to learn about jade, went to study with a talented old teacher. This gentleman put a piece of jade into the boys hand and told him to hold on tight. Then the old man began to talk of philosophy, men, women, the sun and almost everything under it. The procedure was repeated for weeks. The boy became frustrated; when would he be told about jade.
But he was too polite to interrupt his venerable teacher. Then one day the old man put a stone into his hands. The boy called out instantly THAT'S NOT JADE!
