AQUAMARINE CRYSTAL SPECIMEN
A beautiful natural Aquamarine Crystal Specimen. What could be better than a gemstone in its natural crystal form. A well formed and terminated crystal specimen. Colourless and cloudy in colour with natural termination.
Kunar Valley, Afghanistan.
3.5cm x 2.5cm x 1.8cm, 28g.
Beryllium Aluminum Silicate
Beryl is often unknown to the general public. However, it is one of the most important gem minerals. Beryl is colorless in pure form; it is the many different impurities that give beryl its varied coloration. Without these splendid color varieties, beryl would be a rather ordinary gemstone with only average fire and brilliance. Emerald is the green variety and Aquamarine is the blue variety of beryl.
Highly prized and is one of the most valued gemstones. Emerald Green color is the best. The most intense green colored gem. Specimens are often flawed with mineral inclusions and fractures considered part of the stones character. These flaws help determine natural from synthetically produced stones. Uncut emerald specimens are rare on the mineral markets. Even low grade emeralds can carry a high price when cut as gems. Especially hard to find are “in-matrix” specimens.
Crystals glued into a matrix to make constructs or fakes for a deceptive profit. Then sold as an in-matrix specimen with a highly inflated price. Helpful tools for checking are a 10 x loupe, strong light and sometimes a UV light. They sprinkle the matrix dust over the glue so you can’t see what it is. Sneaky sneaky sneaky.
Aquamarine is also a popular gem although it does not command nearly as high a price as its green cousin. Uncut aquamarine specimen crystals are relatively expensive. Large crystals of aquamarine are available on the open market and represent perhaps the largest raw gemstone specimens.
Aquamarine is the blue, or perhaps more correctly, blue-green or aqua variety of the mineral beryl. Other gemstone color varieties that belong to Beryl include Emerald, Morganite, and Heliodor. The colors of Beryl all have names, listed above.
Colored by trace amounts of iron. Aquamarine gemstones are often heat treated. This produces the popular blue-green colors from less desirable yellow or pale stones. Reversing the color to yellow is impossible. The leading producer of aquamarines is the country of Brazil, which has many mines. Pakistan, as well as many U.S. localities, produce wonderful specimens as well. Generally they have hexagonal crystal forms and a few have tabulated hexagonal form.
Some crystals are enormous 9 metres 25 tons. Very hard with fine striated crystal faces. Characteristic of granitic rocks and pegmatites. Also found in very high temperature hydrothermal deposits. Heliodor often fluoresces blue under UV light. Because of its hardness and chemical resistance it remains unaltered in alluvial deposits.
Beryl is an ore for Beryllium.
Beryllium is a chemical element with the symbol Be and atomic number 4. It is a relatively rare element in the universe. Usually occurring as a product of the spallation of larger atomic nuclei that have collided with cosmic rays. Beryllium transforms into heavier elements inside a star. It was once mined from the Triple Chance Mine in Aussie for the Apollo Space Program.
Color is varied and includes emerald green, blue to blue-green, yellow, greenish-gold, red, colorless and pink.
Luster is vitreous.
Transparency: Crystals are transparent to translucent.
Crystal System is hexagonal; 6/m 2/m 2/m
Crystal Habits typically include the hexagonal prism with pincoid terminations. Terminations often modified by many different pyramidal faces. They can sometimes produce a rounded termination in the rough shape of a used pencil eraser.
Cleavage is imperfect in one direction (basal).
Fracture is conchoidal.
Hardness is 7.5 – 8.
Specific Gravity is approximately 2.6 – 2.9 (average)
Streak is white.
Associated Minerals include Micas, Quartz, Euclase, Calcite, Tourmalines, Spodumene, Cassiterite and some Feldspars.
Notable Occurrences include Colombia and some African localities for emerald; Brazil, Russia and Pakistan for aquamarine; California, Brazil, Africa, and many other localities for other beryls.
Best Field Indicators are crystal habit, lack of good cleavage, hardness and color.