Emerald
La Pita Mine, La Pita, MaripÃ, Western Boyacá Province, Boyacá Department, Colombia
1.20 carats
© Rarestone.com
The crystals are usually small with average length of 2 - 5 cm and width of 1 - 1.5 cm. Larger crystals are usually semitransparent to opaque. Flawless faceted emeralds exceeding 5 carats are rather rare.
The emerald is often clouded by inclusions, they are not classified as faults but show the difference between natural and synthetic stone.
Emerald Gemstones by Colour
This table shows the variety of hues this gemstone can be found in. Click on a photo for more information.
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Emerald Gemstones by Size
This table shows distribution of Emerald gemstone sizes that are listed on this site. This can give a good indication as to the general availability of this gemstone in different sizes.
Contributed photos
Lightest:0.10 cts
Heaviest:37.8 cts
Average:2.65 cts
Total photos:92
Do you have a larger Emerald? Why not upload a photo?
Significant stones
Emerald Unguentarium2,860 cts
Mogul Emerald218 cts
Hooker emerald75 cts
| General Information | |||||||||||||||||||||||||||||||||||||||||
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| A variety or type of: | Beryl | ||||||||||||||||||||||||||||||||||||||||
| Chemical Formula |
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| Significant stones | |||||||||||||||||||||||||||||||||||||||||
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| Emerald Treatments | |||||||||||||||||||||||||||||||||||||||||
| Fracture-filling with cedarwood oil is a common clarity treatment, it is not permanent. The filler material can discolour or become damaged. - GIA, 2018 Beware of coated beryl: look for peeled coating (surface-reflecting light) - Blue Chart Gem Identification, Herve Nicolas Lazzarelli, 2010, p 6 Impregnation of the crystal faces with oil is used to conceal minute fractures and improve transparency. Canada balsam, cedar resin, kerosene and other similar materials may be used instead of oil. A technology was developed in Israel, in which fractures were filled with a melt of bismuth and lead under vacuum at high temperature to strengthen raw emerald prior to cutting. - E.Ya. Kievlenko, Geology of gems, 2003, p. 75 | |||||||||||||||||||||||||||||||||||||||||
| Emerald Simulants | |||||||||||||||||||||||||||||||||||||||||
| Glass with groups of gas bubbles creating "fingerprints" - Blue Chart Gem Identification, Herve Nicolas Lazzarelli, 2010, p 6 | |||||||||||||||||||||||||||||||||||||||||
| Synthetic Emerald | |||||||||||||||||||||||||||||||||||||||||
| Synthetic emerald (flux grown) - Colour - green; transparent; Hardness 7.5 - 8; RI 1.553 - 1.580; Birefringence 0.003 - 0.008; Hexagonal; Uniaxial/+; SG 2.63 - 2.69; Inclusions: flux residues, wisp-like flux "feathers" and "veils", phenakite. Synthetic emerald - Colour - green; RI 1.563 - 1.585; Birefringence 0.004 - 0.008; SG 2.66 - 2.72; Inclusions: inhomogeneous growth structure (swirl-like or chevron pattern), phenakite crystals, phenakite nails, iron oxide residues. Synthetic emerald (hydrothermal synthetic emerald overgrowth on colourless beryl) - Colour - green; RI 1.565 - 1.620; Birefringence 0.005 - 0.010; SG 2.66 - 2.71; Inclusions: characteristic pattern of cracks, patchy colour zoning (lighter and darker facets) - Ulrich Henn and Claudio C. Milisenda, Gemmological Tables German Gemmological Association, 2004, p 10 | |||||||||||||||||||||||||||||||||||||||||
| Physical Properties of Emerald | |||||||||||||||||||||||||||||||||||||||||
| Mohs Hardness | 7.5 to 8, Blue Chart Gem Identification (2010) More from other references | ||||||||||||||||||||||||||||||||||||||||
| Specific Gravity | 2.67 to 2.78, Blue Chart Gem Identification (2010) 2.68-Colombia; 2.67-Brazil; 2.68-Zambia/Zimbabwe; 2.70-Afghanistan/Pakistan/India; 2.68-Australia; 2.71-Ural; 2.68-MadagascarMore from other references | ||||||||||||||||||||||||||||||||||||||||
| Tenacity | Brittle, Gems, Sixth Edition (2006) | ||||||||||||||||||||||||||||||||||||||||
| Cleavage Quality | Indistinct, Gemstones of the world (2001) More from other references | ||||||||||||||||||||||||||||||||||||||||
| Fracture | Uneven,Conchoidal, Gemstones of the world (2001) | ||||||||||||||||||||||||||||||||||||||||
| Optical Properties of Emerald | |||||||||||||||||||||||||||||||||||||||||
| Refractive Index | 1.565 to 1.602, Blue Chart Gem Identification (2010) 1.568-Colombia; 1.565-Brazil; 1.580-Zambia/Zimbabwe; 1.578-Afghanistan/Pakistan/India; 1.565-Australia; 1.577-Ural; 1.580-MadagascarMore from other references | ||||||||||||||||||||||||||||||||||||||||
| Optical Character | Uniaxial/-, Blue Chart Gem Identification (2010) | ||||||||||||||||||||||||||||||||||||||||
| Birefringence | 0.004 to 0.010, Blue Chart Gem Identification (2010) 0.005-Colombia; 0.005-Brazil; 1.580-Zambia/Zimbabwe; 0.007-Afghanistan/Pakistan/India; 0.005-Australia; 0.006-Ural; 0.006-MadagascarMore from other references | ||||||||||||||||||||||||||||||||||||||||
| Pleochroism | Strong dichroism: yellow green - blue green, Blue Chart Gem Identification (2010) More from other references | ||||||||||||||||||||||||||||||||||||||||
| Dispersion | 0.014, Gemstones of the world (2001) | ||||||||||||||||||||||||||||||||||||||||
| Colour | |||||||||||||||||||||||||||||||||||||||||
| Colour (General) | Emerald green, green, slightly yellowish-green, Gemstones of the world (2001) More from other references | ||||||||||||||||||||||||||||||||||||||||
| Colour (Chelsea Filter) | Pinkish to "wine red", depending on chromium content (may remain greenish)., Blue Chart Gem Identification (2010) Colombia: wine red (chromium rich); Brazil: green to dark red; Zambia: green to red; Zimbabwe: weak reddish common; Afghanistan/Pakistan: commonly pinkish to "wine red"; India: usually dark green; Australia: brownish, greenish or pinkish; Ural: dark red common | ||||||||||||||||||||||||||||||||||||||||
| Causes of Colour | Green, Cr3+ and/or V3+ in octahedral coordination., Pragmatic Spectroscopy For Gemologists (2011) | ||||||||||||||||||||||||||||||||||||||||
| Transparency | Transparent,Translucent,Opaque, Gemstones of the world (2001) | ||||||||||||||||||||||||||||||||||||||||
| Fluorescence & other light emissions | |||||||||||||||||||||||||||||||||||||||||
| Fluorescence (General) | Usually inert, Blue Chart Gem Identification (2010) | ||||||||||||||||||||||||||||||||||||||||
| Crystallography of Emerald | |||||||||||||||||||||||||||||||||||||||||
| Crystal System | Hexagonal, Blue Chart Gem Identification (2010) | ||||||||||||||||||||||||||||||||||||||||
| Habit | Hexagonal prisms, Gemstones of the world (2001) | ||||||||||||||||||||||||||||||||||||||||
| Geological Environment | |||||||||||||||||||||||||||||||||||||||||
| Where found: | Emeralds are formed by hydrothermal processes associated with magma and also by metamorphism. Deposits are found in biotite schists, clay shales, in limestones, with pegmatites. Mining is nearly from host rock, where the emerald has grown into small veins or on walls of cavities. Alluvial placers are very unlikely to come about as the density of emerald is near that of quartz. Therefore, rare secondary deposits are mostly formed by weathering., Gemstones of the world (2001) | ||||||||||||||||||||||||||||||||||||||||
| Spectrographic Data | |||||||||||||||||||||||||||||||||||||||||
| Calculated Spectra: Click spectra for more information | Emerald - Locality: Synthetic Emerald - Locality: Synthetic (manufactured in China) Emerald - Locality: Muzo, Colombia | ||||||||||||||||||||||||||||||||||||||||
| Emeralds without inclusions are rare and should be considered as highly suspicious. Colombia: 3 phase inclusions (sometimes jagged), pyrite (Chivor), calcite (Muzo), albite crystals. Brazil: tube-like 2 phase inclusions, black chromite and dolomite crystals, mica platelets. Zambia: rectangular shaped multi-phase inclusions, dot-like whitish to brown biotite platelets. Zimbabwe: long, straight and curved amphibole (tremolite) needles. Afghanistan/Pakistan: 2-3 phase inclusions, black chromite inclusions. India: rectangular 2 phase inclusions with "comma" shaped corner. Australia: 2-(3) phase tube-like inclusions parallel to optical axis. 2-(3)-phase secondary healed fractures, tremolite rods, colorless to brown biotite, cassiterite and other guest crystals. Ural: actinolite (tremolite) crystals in "bamboo cane" pattern. Thin liquid films (reflected light). Mica flakes. Madagascar: thin elongated growth tubes, elongated quartz crystals, isometric 2 phase negative crystals, thin films of liquid inclusions - Blue Chart Gem Identification, Herve Nicolas Lazzarelli, 2010, p 6 | |||||||||||||||||||||||||||||||||||||||||
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