Formula Chrysoberyl: Al₂[Be₄]
Mineral class: beryl-aluminates
Crystal system: rhombic
Mohs scale: 8.5
Density (g/cm³): 3.7 - 3.72
Cleavage: different
Colors: golden yellow, greenish, brownish
Luster: vitreous
Fluorescence: -
Pleochroism: slight
Largest Chrysoberyl: 22 cm?
Deposits: Brazil, Sri Lanka, Myanmar, Madagascar, Zimbabwe, Russia
1st Description: 1944

Chrysoberyl Mineral

Origin: Espirito Santo / Brazil

Photo by kind permission of © www.irocks.com, Dr. Robert Lavinsky.

Chrysoberyl

Weight: 1.5 ct

Origin: Brazil

Photo by kind permission of © www.ridderborg.se, Simon Ridderborg.

Chrysoberyl

Weight: 3.72 ct

Origin: Tanzania

Photo by kind permission of © www.multicolour.com, David Weinberg.

Chrysoberyl

Weight: 5.50 ct

Origin: Koslanda / Sri Lanka

Photo by kind permission of © www.wildfishgems.com, Edward Bristol.

Chrysoberyl Mineral

Origin: Espirito Santo / Brazil

Photo by kind permission of © www.irocks.com, Dr. Robert Lavinsky.

Chrysoberyl

Weight: 5,86 ct

Origin: Tanzania

Photo by kind permission of © www.multicolour.com, David Weinberg.

Chrysoberyl

Weight: 12.20 ct

Origin: Tanzania

Photo by kind permission of © www.multicolour.com, David Weinberg.

Chrysoberyl

Weight: 3.42 ct

Origin: Orissa / India

Photo by kind permission of © www.americanthai.com, Scott Davies.

Chrysoberyl

Weight: 2.56 ct

Origin: Tanzania

Photo by kind permission of © www.multicolour.com, David Weinberg.

Chrysoberyl

Weight: 12.99 ct

Origin: Tunduru / Tanzania

Photo by kind permission of © www.multicolour.com, David Weinberg.

Chrysoberyl

Weight: 2.77 ct

Origin: Brazil

Photo by kind permission of © www.irocks.com, Dr. Robert Lavinsky.

Chrysoberyl

Weight: 2.76 ct

Origin: Tanzania

Photo by kind permission of © www.multicolour.com, David Weinberg.

Chrysoberyl Mineral

Origin: Onh Bin Yee Htwet / Le-Oo / Mogok / Myanmar

Photo by kind permission of © www.crystal-treasure.com, Sieghard Ellenberger.

Chrysoberyl

Weight: 3.23 ct

Origin: Tanzania

Photo by kind permission of © www.multicolour.com, David Weinberg.

Chrysoberyl Star

Weight: 1.02 ct

Origin: Sri Lanka

Photo by kind permission of © www.thegemtrader.com, Brad Payne.

Formula Chrysoberyl Cat's Eye: BeAl₂O₄
Mineral class: oxides
Crystal system: orthorhombic
Mohs scale: 8.5
Density (g/cm³): 3.65 - 3.85
Colors: green (in variations), yellow, blue
Fluorescence: ?
Pleochroism: ?
Largest faceted Chrysoberyl cat's eye: 465 ct ("Eye of the Lion") from Sri Lanka
Deposits (according to mindat.org): worldwide

Chrysoberyl Cat's Eye Mineral

Origin: Brazil

Photo by kind permission of © www.TreasureMountainMining.com, Eric Greene.

Chrysoberyl Cat's Eye

Weight: 1,46 ct

Origin: Sri Lanka

Photo by kind permission of © www.multicolour.com, David Weinberg.

Chrysoberyl Cat's Eye

Weight: 1.63 ct

Origin: Madagascar

Photo by kind permission of © www.multicolour.com, David Weinberg.

Chrysoberyl Cat's Eye

Weight: 1,89 ct

Origin: Madagascar

Photo by kind permission of © www.multicolour.com, David Weinberg.

Chrysoberyl Cat's Eye

Weight: 1,51 ct

Origin: Sri Lanka

Photo by kind permission of © www.multicolour.com, David Weinberg.

Chrysoberyl Cat's Eye

Weight: 0,32 ct

Origin: Orissa / India

Photo by kind permission of © www.irocks.com, Dr. Robert Lavinsky.

Chrysoberyl Cat's Eye

Weight: 4.24 ct

Origin: India

Photo by kind permission of © www.thegemtrader.com, Brad Payne.

Chrysoberyl Cat's Eye

Weight: 4.23 ct

Origin: East Africa

Photo by kind permission of © www.multicolour.com, David Weinberg.

Chrysoberyl Cat's Eye

Weight: 43.29 ct

Origin: Sri Lanka

Photo by kind permission of © www.online-edelstein.de, Timo Klopp.

Chrysoberyl Cat's Eye

Weight: 5.15 ct

Origin: Sri Lanka

Photo by kind permission of © www.djraregems.com, John & Donna Rhoads.

Chrysoberyl Cat's Eye

Weight: 1.72 ct

Origin: Madagascar

Photo by kind permission of © www.multicolour.com, David Weinberg.

Chrysoberyl Cat's Eye

Weight: 4,38 ct

Origin: Sri Lanka

Photo by kind permission of © www.djraregems.com, John & Donna Rhoads.

Chrysoberyl Cat's Eye

Weight: 1.58 ct

Origin: Hatton / Sri Lanka

Photo by kind permission of © www.wildfishgems.com, Edward Bristol.

Chrysoberyl Cat's Eye

Weight: 1.73 ct

Origin: Hatton / Sri Lanka

Photo by kind permission of © www.wildfishgems.com, Edward Bristol.

Formula Vanadium Chrysoberyl: BeAl₂O₄
Vanadis Chrizoberilas, Vanadium Chrysobéryl, Vanadium Chrysoberyll, Wanad Chryzoberyl, Vanadio Crisoberillo, Vanádium Krizoberill, Vanaadium Krüsoberüll, Vanadiini Krysoberylli, Ванадий Хризоберилл, バナジウム クリソベリル,
바나듐 금록석, 釩 金綠玉, วาเนเดียม อะเลกซานไดรต์, ונדיום כריזובריל
Mineral class: oxides
Crystal system: orthorhombic
Mohs scale: 8.5
Density (g/cm³): 3.7
Colors: green (in variations)
Fluorescence: ?
Pleochroism: ?
Largest faceted Vanadium Chrysoberyl: ?
Deposits: Brazil, Italy, Madagascar, Myanmar, Russia, Sri Lanka, Tanzania, USA, Zimbabwe

Vanadium Chrysoberyl Mineral

Origin: Kyauk Sin Mine / Kyat Pin / Mogok / Myanmar

Photo by kind permission of © www.crystal-treasure.com, Sieghard Ellenberger.

Formula Alexandrite: BeAl₂O₄
Alejandrita, Aleksandriidina, Aleksandriitti, Aleksandritas, Aleksandryt, Alessandrite, Alexandriet, Alexandrit, Alexandrita, Александрит, アレキサンドライト, 亞歷山大石
Mineral class: oxides
Crystal system: orthorhombic
Mohs scale: 8.5
Density (g/cm³): 3.7
Colors: green (in variations) to blueish / violet in daylight, orange to reddish / violet in artificial light. The color change effect is based on traces of chromium which partially replaces the aluminium.
Fluorescence: red
Pleochroism / Trichroism: strong. X= red - violet, Y= orange, Z= green
Ural / Russia: profound red - yellow orange - green blue
Andrapradesh / India:
Sri Lanka: red - orange - green
Mogok / Myanmar: purple - grass green - green blue
Minas Gerais / Brazil: dark red - orange-yellow - green
Tunduru / Tanzania:
"Alexandrite effect":
Alexandrite is a trichroic gemstone which may absorb and reflect light differently in each of its three optical directions. However, it is not the trichroism that is responsible for the remarkable change. The color change phenomena is a result of the presence of Cr³⁺ ions, and the way they are absorbed and reflected ... In alexandrite, where the Cr absorption band is at 580nm and right between ruby red (550nm) and green emerald (600nm), the stone is balanced between them. When the light is balanced (daylight), the stone will be green but when the light source is reddish (incandescent), the stone appears red.
(Source: www.multicolour.com)
Largest Alexandrite: rough: "The Saurer Alexandrite" from Brazil (122,400 ct). Faceted: 66 ct, at the Smithsonian Institution in Washington D.C. (source: www.alexandrite.net)
Deposits: Brazil, India, Russia, Tanzania, Australia, Madagascar, Myanmar, Sri Lanka, USA, Zimbabwe
History:
• Discovery: 1834 at the emerald mines on the Takowaja river in the Ural Mountains (Russia) by the Finnish mineralogist of Tsar Alexander II., Dr. Nils Nordenskjold (after Witali Repej / Ukraine).
• Naming in honor of Tsar Alexander II. in 1842. Alexandrite was named on the occasion of the full legal age of the tsar.
• Discovery of valuable alexandrite in 1987 at Hematita / Minas Gerais / Brazil.
• Resumption of the Takowaja river mine(s) in 1995.
• Discovery of alexandrit deposits in the Araku Valley in Andhra Pradesh / India in 1996.
• Destruction of the coastal mines in India by the tsunami in 2004.

Alexandrite Mineral

Origin: Malyshevskoe / Yekaterina Oblast / Ural Mountains / Russia

Photo by kind permission of © www.exceptionalminerals.com, Kevin Ward.

Alexandrite

Weight: 0.12 ct

Origin: Russia

Photo by kind permission of www.edelsteine.at, Thomas Pfneisl.

Alexandrite

Weight: 0.21 ct

Origin: Russia

Photo by kind permission of www.edelsteine.at, Thomas Pfneisl.

Alexandrite Mineral

Origin: Malyshevskoe / Yekaterina Oblast / Ural Mountains / Russia

Photo by kind permission of © www.irocks.com, Dr. Robert Lavinsky.

Alexandrite

Weight: 10.50 ct

Origin: Brazil

Photo by kind permission of www.edelsteine.at, Thomas Pfneisl.

Alexandrite

Weight: 0.17 ct

Origin: Malishevo Mine / Ural Mts. / Russia

Photo by kind permission of www.edelsteine.at, Thomas Pfneisl.

Alexandrite

Weight: 0.33 ct

Origin: India

Photo by kind permission of www.gemfrance.com, Dr. Laurent Sikirdji.

Alexandrite

Weight: 3.20 ct

Origin: Tunduru / Tanzania

Photo by kind permission of www.multicolour.com, David Weinberg.

Alexandrite

Weight: 3.54 ct

Origin: Tanzania

Photo by kind permission of www.djraregems.com, Donna & John Rhoads.

Alexandrite

Weight: 3.03 ct

Origin: Tunduru / Tanzania

Photo by kind permission of www.multicolour.com, David Weinberg.

Alexandrite

Weight: 2.15 ct

Origin: Andrapradesh / India

Photo by kind permission of www.multicolour.com, David Weinberg.

Alexandrite

Weight: 1.04 ct

Origin: Tanzania

Photo by kind permission of www.djraregems.com, Donna & John Rhoads.

Alexandrite

Weight: 8.66 ct

Origin: Tunduru / Tanzania

Photo by kind permission of www.multicolour.com, David Weinberg.

Alexandrite

Weight: 2.16 ct

Origin: Andrapradesh / India

Photo by kind permission of www.multicolour.com, David Weinberg.

Alexandrite

Weight: 1.60 ct

Origin: Tunduru / Tanzania

Photo by kind permission of www.multicolour.com, David Weinberg.

Alexandrite Cat's Eye

Weight: 0.25 ct

Origin: Hematita Mine / Nova Era / Minas Gerais / Brazil

Photo by kind permission of www.edelsteine.at, Thomas Pfneisl.