AGATE: Hardness: 6.5
Agate is named after a river in Sicily, called ACHATES, where it was found in fourth century BC. Agate is the most common form of chalcedony, and is a versatile commercial stone. Typically, in the centre of the rock, there is a cavity in which crystals often form. An agate gem with a cavity is called a Geode. Agate gems are found lining cavities of volcanic rocks worldwide. The rock formation in which the Agate is found is approximately 50 million years old and the Agate you see is found in Brazil. The mines have been worked since the 1880’s and provide a large percentage of the world’s supply of agate gems. While thousands of tons of agates are mined every year, only a small portion is suitable to be used for the products on display. AMAZONITE:
The name is taken from that of the Amazon River from which certain green stones were formerly obtained. Amazonite is a mineral of limited occurrence almost exclusively from Russia though high-quality crystals have been obtained from Pike’s Peak, Colorado. Because of its bright green colour when polished, Amazonite is sometimes cut and used as a gemstone. The blue-green colour is due to small quantities of lead and water in the feldspar.
AMETHYST: Hardness: 7
Quartz is one of the most widely distributed minerals. Amethyst is the most valuable type of the quartz gemstones. It is characterized by its shades of purple, caused by iron. Amethyst is named after a maiden in Greek legend whose name was “AMETHYST”, which in Greek means “NOT DRUNKEN” and was worn as an amulet against drunkenness in ancient times. Amethyst forms in volcanic rock in the form of crystals. It can be found in Canada, Mexico, Africa, and the United States but the best sources of amethyst gemstones are in Brazil and Uruguay. Most of the world’s supply comes from the same general area of Brazil and Uruguay.
Ammonites flourished in the ancient oceans, near the continents, at all water depths. They were carnivorous, probably very agile, and intelligent, like their modern relative the NAUTIILUS. The smallest ammonite species were less than an inch in size, the larger, coiled species reached more than 9 feet (3m) across.
KYANITE: Hardness: 4.5 - 5
Kyanite is a polymorph, with two other minerals: ARDALUSITE and SILLIMANITE. A polymorph is a mineral that shares the same chemistry but a different crystal structure with another, or other minerals. Kyanite is an attractive mineral that has a near sapphire-like blue colour. Kyanite has unique characteristics in which it has a wide variation of hardness in the same crystal.
Aquamarine is a gemstone- quality transparent variety of beryl. Colours vary: yellow beryl, called heliodor; rose pink beryl - morganite and white beryl - goshenite are known. Aquamarine has a hexagonal crystal structure and a chemical formula of Be(3)A1(s)Si(6)O(18). It has a specific gravity of 2.68 to 2.74 and a MOHS hardness of 7.5 to 8. It occurs in Russia, the U.S, Brazil, Zambia and other African locations. Aquamarine is the official state gem of Colorado.
Citrine is a crystalline quartz from Brazil with a brownish-yellow colour, sometimes referred to as false topaz. The colours in quartz are usually caused by a mineral impurity. Sometimes you can see air bubbles and traces of other minerals trapped within the crystals. Citrine druze has a soft base and tends to crumble. Handle with care.
CRYSTAL POINTS (CLUSTERS): Hardness: 7
Quartz includes a variety of stones. Colourless quartz, or crystal quartz, is the most common. The word “CRYSTAL” comes from the Greek word for “ICE” and was believed to be eternally frozen. The single quartz crystal is a six-sided prism, however this is not always how it is formed. Sometimes it is found in veins, seams or pockets of rock. It is popular for carving objects and making crystal balls. Quartz is used for optical and technical purposes, but only 10% is pure enough to use for this purpose. The major supplier of crystal quartz is Brazil, but it is found abundantly throughout the world including the United States.
EMERALD: Hardness: 7.5-8
Emerald is a variety of the mineral beryl; coloured green by trace amounts of chromium and sometimes iron. It is highly prized as a gemstone, often made more so by inclusions. Emerald is the birthstone for May. Be3 A1s Si6-18
These arrowheads are replicas of those used by the Indians of North America, from the recent past of 10,000 years ago. They are not from any archeological sites. Stones used for arrowheads are flint, which is brown and grey, and obsidian, which is black. Be careful!!! These arrowheads are sharp. Remember the Indians used them for hunting.
These stream-tumbled pebbles are collected in Brazil, then cut out and polished on one side so you can see the interesting interiors. You can choose from Amethyst, Clear Quartz, Rose Quartz, and Smoky Quartz. These are all quartz minerals with a chemical composition of Si0 and a hardness of 7 on the MOHS scale. The inclusions you can see in these stones are made from many different minerals. To clearly view these, place a small light under the stone.
Fuchsite is a dark green variety of muscovite. It can have a wonderful dark emerald colour that can have a beautiful sparkly shine if the crystals are small. It is often found in compact masses with small crystals. The green colour is the result of chromium impurities. KA12(A1 Si3O10)(F,OH)2
Commonly referred to as “FOOLS GOLD”, Pyrite is a brass-yellow, metallic crystal structure that resembles gold. Unfortunately, it cannot be used in jewelry in the same manner as gold because it easily turns to powder. The Incas used Pyrite’s reflective quality for mirrors. When struck with a hammer, sparks are emitted, thus giving it its name that means “FIRE” in Greek. Pyrite is found in many environments throughout the world, including Mexico, Peru, and the United States. Fes2
GEODE HALVES (OCO’S): Hardness: 6.5
Geode halves, or Oco’s, which is the word used in Brazil where they are found, are tiny agate nodules with a geode center. Agate is named after a river in Sicily, called Achates, where it was found in the fourth century B.C. In the centre of the rock, where there is a cavity, crystals often form, thus the name 'Geode'.
The formation in which the Geodes are found is 50 million years old and located in many areas, including the United States. The Oco’s have been gathered by farmers for many years. After the crops are harvested and the farmers are unable to work, the fields are tilled under allowing the Oco’s to appear. They are then gathered and sold for cutting into the Geode half as you see now. Si02
Lepidolite is an uncommon mica and has only in the past decade become available in the mineral market in large quantities. Lepidolite is an ore of lithium and forms in granite masses that contain a substantial amount of lithium. The typical violet to pink colour of lepidolite is characteristic and is the only field test available to identify lepidolite from other micas. Lepidolite, like other micas, has a layered structure of lithium aluminum silicate sheets weakly bonded together by layers of potassium ions. These potassium ion layers produce the perfect cleavage. KLi2A1(A1,Si)3O10(F,OH)2
Calcite is a very common mineral and is the main constituent of limestone. Calcite occurs from solution in limestone and basalt cavities found in hydrothermal veins. Crystals of calcite may be found in many different colours: orange, blue, yellow, pink, and clear.
While the colour of this calcite is natural, it has been treated to give it a smooth glossy finish. This specimen of calcite is found predominately in Mexico, and also in the United States. CaCO3
Mica is a generic term applied to a group of complex aluminosilicate minerals having a sheet of plate like structure with different composition and physical properties. All mica form flat six-sided monoclinic crystals with a remarkable cleavage in the direction of large surfaces, which permits them to easily split into optically flat films. When split into thin films, they remain tough and classic even at high temperature. Mica possesses some of the most outstanding combinations of chemical, physical, electrical, thermal and mechanical properties which are not found in any other mineral.
FOSSILIZED SHARK TEETH:
The Carchardodon Megalodon, a giant white shark and distant cousin of the present “Great White”, lived during the mioene epoch. These fossilized shark’s teeth found today are approximately 18 million years old. They are one of the most abundant fossils in the fossil record; however, rarely, if ever are fossilized. Shark skeletons are found because their bodies are composed mainly of cartilage. This shark’s tooth was collected in the coastal region of South Carolina, as far as 30 miles inland and at a depth of 15 to 20 feet. The size of the shark can be estimated by the size of the tooth.
A general rule of thumb is ten feet of shark for each inch of tooth. Megalodon reached a length of 60 feet or more as indicated by the 61/2 to 7 inch teeth that have been found.
About Sharks “Teeth”!
Sharks first appeared about 370 million years ago. Sharks belong to a large group of fish that have a skeleton made of cartilage instead of bone. Cartilage is a firm whitish or yellowish tissue. The only fossilized remains of ancient sharks are mostly their teeth; in a few other cases, we come across shark vertebra “phosphate mines of Morocco”. The teeth grew in constantly to replace older teeth that wore out. Some ancient sharks grew as long as 64 feet.
The Tourmaline mineral group is a complex silicate of aluminum and boron. Its composition varies widely with sodium, calcium, iron, magnesium, lithium and other elements. Tourmaline occurs as long and slender to thick prismatic and columnar crystals. Tourmaline has a wide variety of colours, black to bluish-black, deep brown, yellow, blue, green, red and pink.
The Orthoceras is a straight-shelled Cephalopoda which means “head foot”. It is a relative of the squid, cuttlefish, octopod, and the nautilus that can be found in the oceans today. This particular type of Orthoceras lived in the Devonian Period, 245 to 395 million years ago and was unearthed in the Sahara Desert, Morocco.
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