Not required for students
LI> Beryl crystals may be enormous !!
Largest emerald: 7025 ct, discovered 1969
Viennese treasury: jug 12 cm high, 2205 ct, cut from single emerald
Largest cut crystal of aquamarine: (1910, Brazil) 243 lb (110.5 kg)
=18" x 15.5"
Emeralds can differ greatly in price and size
- e.g., Albany, Maine: xal 27 ft long and weighted 25 tons !
- "Mogul" emerald 217.8 ct 17th Century Colombian (taken to India)
- "Patricia" emerald, discovered 1920, sold in 1921 for US$60,000
(discoverer got US$10-)
- Of the beryl varieties, emerald is usually flawed,
but aquamarine is usually flawless
- Beryl, an
aluminosilicate mineral, is the principal ore of the rare element beryllium
- Long prized as
various gemstones, notably the deep-green emerald, the pale blue green
aquamarine, the pink
morganite, and the golden heliodore, beryl is easily distinguished by its
long, six sided prismatic
crystals (hexagonal system) but also forms compact to coarsely granular masses
common material is whitish to green and is subtranslucent;
gem material is transparent
vitreous. Most beryl is found in pegmatite dikes, where large
crystals are intergrown with
quartz and feldspar, but the emerald variety also occurs in altered limestone
and in various
- Crystal size ranges from tiny to enormous. A crystal weighing 200
tons was mined in Minas Gerais, Brazil, and crystals about 6 m. (20 ft) long and 2 m (7 ft)
across have been found in the Black Hills of South Dakota and in Albany, Maine.
- Common beryl
has been mined for beryllium since 1925, notably in Brazil, the major producer.