1.9M+ REVIEWS | 1000+ NEW GEMS DAILY |
$38.00 USD
Prix
1879
3

Spinel, 1.09ct, looking almost like a zircon but more beautiful!

UGS
Dimensions (mm)
6.400 x 5.600 x 4.160mm
Poids (cts)
1.090
Treatment
No Treatment
Clarity
VS
Taper
Faceted
Couleurs

Spinel ( /spɪˈnɛl/) is the magnesium/aluminium member of the larger spinel group of minerals. It has the formula MgAl2O4 in the cubic crystal system. Its name comes from the Latin word "spinella", which means spine in reference to its pointed crystals.

Spinel crystallizes in the isometric system; common crystal forms are octahedra, usually twinned. It has an imperfect octahedral cleavage and a conchoidal fracture. Its hardness is 8, its specific gravity is 3.5–4.1, and it is transparent to opaque with a vitreous to dull luster. It may be colorless, but is usually various shades of pink, rose, red, blue, green, yellow, brown, black, or (uncommon) violet. There is a unique natural white spinel, now lost, that surfaced briefly in what is now Sri Lanka. Some spinels are among the most famous gemstones; among them are the Black Prince's Ruby and the "Timur ruby" in the British Crown Jewels, and the "Côte de Bretagne", formerly from the French Crown jewels. The Samarian Spinel is the largest known spinel in the world, weighing 500 carats (100 g).

The transparent red spinels were called spinel-rubies or balas rubies. In the past, before the arrival of modern science, spinels and rubies were equally known as rubies. After the 18th century the word ruby was only used for the red gem variety of the mineral corundum and the word spinel came to be used. "Balas" is derived from Balascia, the ancient name for Badakhshan, a region in central Asia situated in the upper valley of the Panj River, one of the principal tributaries of the Oxus River. Mines in the Gorno Badakhshan region of Tajikistan constituted for centuries the main source for red and pink spinels.

Spinel is found as a metamorphic mineral, and also as a primary mineral in rare mafic igneous rocks; in these igneous rocks, the magmas are relatively deficient in alkalis relative to aluminium, and aluminium oxide may form as the mineral corundum or may combine with magnesia to form spinel. This is why spinel and ruby are often found together. The spinel petrogenesis in mafic magmatic rocks is strongly debated, but certainly results from mafic magma interaction with more evolved magma or rock (e.g. gabbro, troctolite).

Spinel, (Mg,Fe)(Al,Cr)2O4, is common in peridotite in the uppermost Earth's mantle, between approximately 20 km to approximately 120 km, possibly to lower depths depending on the chromium content. At significantly shallower depths, above the Moho, calcic plagioclase is the more stable aluminous mineral in peridotite while garnet is the stable phase deeper in the mantle below the spinel stability region.

Spinel, (Mg,Fe)Al2O4, is a common mineral in the Ca-Al-rich inclusions (CAIs) in some chondritic meteorites.

Spinel has long been found in the gemstone-bearing gravel of Sri Lanka and in limestones of the Badakshan Province in modern-day Afghanistan and Tajikistan; and of Mogok in Myanmar. Over the last decades gem quality spinels are found in the marbles of Lục Yên District (Vietnam), Mahenge and Matombo (Tanzania), Tsavo (Kenya) and in the gravels of Tunduru (Tanzania) and Ilakaka (Madagascar).

Since 2000 in several locations around the world have been discovered spinels with unusual vivid pink or blue color. Such "glowing" spinels are known from Mogok (Myanmar), Mahenge plateau (Tanzania), Lục Yên District (Vietnam) and some more localities. In 2018 bright blue spinels have been reported also in the southern part of Baffin Island (Canada). The pure blue coloration of spinel is caused by small additions of cobalt.



Shipping: For special requests such as express delivery please contact me. For lost stones the seller is not liable, therefore an additional insurance is recommended. Right of return within two weeks after receiving the shipment. Payment via PayPal, Credit Card, or Bank transfer is possible. For the shipping I generally use: Austrian Post or FedEx. Unfortunately from Austria only DHL "express" is possible.

Please pay your stones in between five days or contact me. Otherwise I need to cancel the deal.

If there is anything you shouldn't be satisfied with please just let me now and we will find a way to solve every problem. My aim is to make you happy with beautiful stones of good quality, good communication is the easiest way to find a solution!



Fournisseur d'expédition Expédition vers :pays Expédition dans le reste du monde
Standard Shipping - Tracked $8.00 / : jours jours $15.00 / : jours jours
:pays
:fournisseur bénéficie d'une réduction de :prix sur les commandes avec :quantité ou plus d'articles
Reste du monde
:fournisseur bénéficie d'une réduction de :prix sur les commandes avec :quantité ou plus d'articles
FedEx $27.00 / : jours jours $46.00 / : jours jours
:pays
:fournisseur bénéficie d'une réduction de :prix sur les commandes avec :quantité ou plus d'articles
Reste du monde
:fournisseur bénéficie d'une réduction de :prix sur les commandes avec :quantité ou plus d'articles
Express Shipping $36.00 / : jours jours $70.00 / : jours jours
:pays
:fournisseur bénéficie d'une réduction de :prix sur les commandes avec :quantité ou plus d'articles
Reste du monde
:fournisseur bénéficie d'une réduction de :prix sur les commandes avec :quantité ou plus d'articles
Registered Shipping $9.00 / : jours jours $16.00 / : jours jours
:pays
:fournisseur bénéficie d'une réduction de :prix sur les commandes avec :quantité ou plus d'articles
Reste du monde
:fournisseur bénéficie d'une réduction de :prix sur les commandes avec :quantité ou plus d'articles
Standard Shipping - Untracked $5.00 / : jours jours $13.00 / : jours jours
:pays
:fournisseur bénéficie d'une réduction de :prix sur les commandes avec :quantité ou plus d'articles
Reste du monde
:fournisseur bénéficie d'une réduction de :prix sur les commandes avec :quantité ou plus d'articles

stonehengejpd
stonehengejpd
Selling all kind of gems, great quality at affordable prices, based in the heart of Europe! In case you may have special wishes just let me know :-) If you shouldn´t be satisfied with an order please do not give a negative feedback just let me know and there is always a way to find a solution that everybody is happy!
:ville Pays
Vérifié
: Retour total
:note% Note

smoky
Positif
il y a 1 mois
Rhodolite pair: 0.95ct, oval shaped sunset coloured stones!
Rhodolite pair: 0.95ct, oval shaped sunset coloured stones!
wrong
Positif
il y a 1 mois
Prasiolite, 1.325ct, brilliant cut, good shape but not very green.
Prasiolite, 1.325ct, brilliant cut, good shape but not very green.
A lovely stone.
smoky
Positif
il y a 1 mois
Ruby, 0.74ct, nice little heated gemstone for a single dollar!
Ruby, 0.74ct, nice little heated gemstone for a single dollar!
smoky
Positif
il y a 1 mois
Grandiderite, 0.475ct, good colour, fine cut, awesome stone !
Grandiderite, 0.475ct, good colour, fine cut, awesome stone !
toutou
Positif
il y a 1 mois
Spinel, 0.35ct, tiny little gem from Ceylon!
Spinel, 0.35ct, tiny little gem from Ceylon!
item is ok, thanks

Audit

Le programme Gemstone Sheriff permet à nos membres de demander un audit sur n'importe quel produit, qui est complété par une Gemologist indépendante qui évalue l'exactitude de la description et des images de l'article.

Les détails d'expédition

Expédition:
$15.00 :compter les jours via Standard Shipping - Tracked
Expédié depuis:
Austria

Options de paiement

  • paypal
  • stripe
  • escrow
Ce vendeur ajoute 20.00% tax aux transactions dans Austria.

Aperçu

Type d'inscription : Standard
Identifiant du produit : 1962755
Départs : 29th November 2023 08:00 pm PST
* Tous les prix sont en :devise