2M+ REVIEWS | 1000+ NEW GEMS DAILY |

You have not bid on this auction.

$14.00
Current Bid
0
Bids
Closed
20/08/2021 03:29 pm
0
92
1

Sphene, 1.13ct, triangle shape, great colours super stone!

SKU
Dimensions (mm)
6.700 x 6.300 x 3.600mm
Weight (cts)
1.130
Clarity
VS, SI
Shape
Triangle
Type
Faceted
Colours

Titanite, or sphene (from the Greek sphenos (σφηνώ), meaning wedge), is a calcium titanium nesosilicate mineral, CaTiSiO5. Trace impurities of iron and aluminium are typically present. Also commonly present are rare earth metals including cerium and yttrium; calcium may be partly replaced by thorium.

The International Mineralogical Association Commission on New Minerals and Mineral Names (CNMMN) adopted the name titanite and "discredited" the name sphene as of 1982, although commonly papers and books initially identify the mineral using both names. Sphene was the most commonly used name until the IMA decision, although both were well known. Some authoritiesthink it is less confusing as the word is used to describe any chemical or crystal with oxidized titanium such as the rare earth titanate pyrochlores series[11] and many of the minerals with the perovskite structure. The name sphene continues to be publishable in peer-reviewed scientific literature, e.g. a paper by Hayden et al. was published in early 2008 in the journal Contributions to Mineralogy and Petrology. Sphene persists as the informal name for titanite gemstones.

Titanite, which is named for its titanium content, occurs as translucent to transparent, reddish brown, gray, yellow, green, or red monoclinic crystals. These crystals are typically sphenoid in habit and are often twinned. Possessing a subadamantine tending to slightly resinous luster, titanite has a hardness of 5.5 and a weak cleavage. Its specific gravity varies between 3.52 and 3.54. Titanite's refractive index is 1.885–1.990 to 1.915–2.050 with a strong birefringence of 0.105 to 0.135 (biaxial positive); under the microscope this leads to a distinctive high relief which combined with the common yellow-brown colour and lozenge-shape cross-section makes the mineral easy to identify. Transparent specimens are noted for their strong trichroism, the three colours presented being dependent on body colour. Owing to the quenching effect of iron, sphene exhibits no fluorescence under ultraviolet light. Some titanite has been found to be metamict, in consequence of structural damage due to radioactive decomposition of the often significant thorium content. When viewed in thin section with a petrographic microscope, pleochroic halos can be observed in minerals surrounding a titanite crystal.

Titanite occurs as a common accessory mineral in intermediate and felsic igneous rocks and associated pegmatites. It also occurs in metamorphic rocks such as gneiss and schists and skarns. Source localities include: Pakistan; Italy; Russia; China; Brazil; Tujetsch, St. Gothard, Switzerland; Madagascar; Tyrol, Austria; Renfrew County, Ontario, Canada; Sanford, Maine, Gouverneur, Diana, Rossie, Fine, Pitcairn, Brewster, New York and California in the US.

Titanite is a source of titanium dioxide, TiO2, used in pigments.

As a gemstone, titanite is usually some shade of chartreuse, but can be brown or black. Hue depends on Fe content, with low Fe content causing green and yellow colours, and high Fe content causing brown or black hues. Zoning is typical in titanite. It is prized for its exceptional dispersive power (0.051, B to G interval) which exceeds that of diamond. Jewelry use of titanite is limited, both because the stone is uncommon in gem quality and is relatively soft.

Titanite can also be used as a U-Pb geochronometer, specifically in metamorphic terranes.  

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 aren´t 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 understand the others´ needs.

 


Shipping provider Shipping to Austria Shipping to rest of world
Standard Shipping - Tracked $8.00 / 3 days $15.00 / 21 days
Austria
Standard Shipping - Tracked is discounted to $15.00 on orders with 3 or more items
Rest of the world
Standard Shipping - Tracked is discounted to $17.00 on orders with 3 or more items
FedEx $27.00 / 2 days $46.00 / 5 days
Austria
FedEx is discounted to $26.00 on orders with 2 or more items
Rest of the world
FedEx is discounted to $45.00 on orders with 2 or more items
Express Shipping $36.00 / 2 days $75.00 / 5 days
Austria
Express Shipping is discounted to $40.00 on orders with 3 or more items
Rest of the world
Express Shipping is discounted to $65.00 on orders with 3 or more items
Registered Shipping $9.00 / 7 days $16.00 / 21 days
Austria
Registered Shipping is discounted to $15.00 on orders with 3 or more items
Rest of the world
Registered Shipping is discounted to $15.00 on orders with 3 or more items
Standard Shipping - Untracked $5.00 / 3 days $13.00 / 28 days
Austria
Standard Shipping - Untracked is discounted to $15.00 on orders with 3 or more items
Rest of the world
Standard Shipping - Untracked is discounted to $13.00 on orders with 3 or more items

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!
Graz, Austria
Verified
1287 Feedback

  • mattosh666
    mattosh666
    Positive

    Thank you! So beautiful. Starting following you. Definitely doing more business

  • kathmedrn
    kathmedrn
    Positive

    Such a beautiful stone! Prettier than the pic!

Bids History (0)
No bids yet.

Why are users outbidding themselves?

When a bid is placed, this is the maximum amount a user is willing to bid for the product. Our system will then automatically bid on that users behalf, incrementally increasing the bid to maintain their position as the highest bidder, up to the specified maximum.

When there is an icon indicating 'Auto Bid,' it means our system is actively placing bids for the user based on their maximum bid. This may appear as if users are outbidding themselves, but it's simply a result of the system updating the bid to reflect the users maximum limit.

Audit

The Gemstone Sheriff program allows our members to request an audit on any product, which is completed by an independent Gemologist who assesses the accuracy of the item description and pictures.

Shipping Details

Shipping:
$15.00 21 days via Standard Shipping - Tracked
Ships from:
Austria

Payment Options

  • paypal
  • stripe
  • escrow
  • gempay
This seller adds 20.00% tax to transactions in Austria.

Overview

Listing Type : Standard
Product ID : 1537902
Starting Bid : $14
Starts : 24th July 2021 08:29 am AEST
Ends : 21st August 2021 08:29 am AEST
* All prices are in USD