Emerald
| Emerald | |
|---|---|
_-2.jpg) Emerald crystals from Muzo, Colombia | |
| General | |
| Category | Beryl variety |
| Formula (repeating unit) | Be3Al2(SiO3)6 |
| Crystal symmetry | (6/m 2/m 2/m) – Dihexagonal Dipyramidal |
| Unit cell | a = 9.21 Å, c = 9.19 Å; Z = 2 |
| Identification | |
| Molecular mass | 537.50 |
| Color | Green shades |
| Crystal habit | Massive to well Crystalline |
| Crystal system | Hexagonal (6/m 2/m 2/m) Space group: P6/mсc |
| Cleavage | Imperfect on the [0001] |
| Fracture | Conchoidal |
| Mohs scale hardness | 7.5–8 |
| Luster | Vitreous |
| Streak | White |
| Diaphaneity | Transparent to opaque |
| Specific gravity | Average 2.76 |
| Optical properties | Uniaxial (-) |
| Refractive index | nω = 1.564–1.595, nε = 1.568–1.602 |
| Birefringence | δ = 0.0040–0.0070 |
| Ultraviolet fluorescence | None (some fracture filling materials used to improve emerald's clarity do fluoresce, but the stone itself does not) |
| References | [1] |
An emerald is a mineral gemstone and a variety of beryl. It is the birthstone of someone whose birthday is in the month of May. It is a green crystal. The emerald is one of the most valuable gems, along with the ruby, the opal, topaz, the diamond, and a sapphire.
Etymology
[change | change source]The word emerald comes from Vulgar Latin. The word was Esmaralda/Esmaraldus, a different way of saying the Latin word Smaragdus, which came from the Greek, σμάραγδος (smaragdos; "green gem").[2][3] It first came from a Semitic word, izmargad (אזמרגד). This meant "emerald" or "green".[2] The name could also be related to the Semitic word baraq (בָּרָק ;البُراق; "lightning" or "shine") (c.f. Hebrew: ברקת bareqeth and Arabic: برق, barq, "lightning"). It is where the Persian (زمرّد zomorrod), Turkish (zümrüt), Sanskrit (मरग्दम् maragdam) and Russian (изумруд; izumrúd) words came from.[3]
Properties
[change | change source]Emeralds, like other colored gemstones, are mainly evaluated based on four factors: color, clarity, cut, and carat weight. Among these, color is the most important. A high-quality emerald should have a rich, pure green color along with good transparency.[4]
Emerald is a member of the beryl family and is considered one of the traditional four precious gemstones, along with diamond, ruby, and sapphire.[5]
The green color of an emerald comes from trace elements such as chromium, vanadium, and iron. The type and amount of these elements determine the exact shade and intensity of the emerald’s green color.[6]
Related pages
[change | change source]References
[change | change source]- ↑ "Emerald at Mindat". Mindat.org. 2010-07-19. Retrieved 2010-07-30.
- 1 2 Fernie M.D., W.T. (1906). Precious Stones for Curative Wear. John Wright. & Co.
- 1 2 "Online Etymology Dictionary". etymonline.com. Retrieved 15 April 2010.
- ↑ "Emerald Quality Factors".
- ↑ "Emerald Value, Price, and Jewelry Information". International Gem Society. 2022-11-01. Retrieved 2026-08-13.
- ↑ "Emerald Gemstone". MyRatna. Retrieved 2026-08-13.
