search
  • Sign In
    Sign Up
  • English speaking customer support only

    Toll Free - USA & Canada only:
    1-800-464-1640

    International:
    +66-39303404

  • Change Language
  • USD

Lovely Gemstone Luster - GemSelect Newsletter

Gemstone Luster: Cabochon Collection
Gemstone Luster: Collection of Cabochons
Shop Gemstone Cabochons

Gemstone luster is perhaps one of the most underrated optical properties when it comes to the appearance of gemstones. It's one of the many terms you'll come across when reading or discussing gems with friends or colleagues. It may not sound so important, but this visible shine (or lack of) can often affect the value of a gemstone just as brilliance and fire can.

What is Gemstone Luster?

Luster is a term that's used to describe how gemstones look or appear, but what exactly is the difference between luster and all the other terms used to describe the appearance of gemstones? Luster refers to the way light reflects from the surface of a gemstone. It's essentially the opposite of brilliance, which is the way light reflects from the interior of a stone.

Pearls, cabochons, and opaque gemstones are usually graded by luster, whereas faceted gems are typically graded by their brilliance. However, even faceted stones can lack the shiny luster and appearance without a good polishing. This is why it's important that every gemstone is given an excellent polish in order to get the most value out of them. A poorly polished gem will simply lack the lustrous look as one that has been given an expert polishing.

Faceted Pyrite With Metallic Luster
Pyrite With Metallic Luster
Shop Pyrite Gems

When it comes to minerals, there are only two main types of luster: metallic and non-metallic. Unfortunately, when it comes to gemstones, it's not that simple. From bright to dull, gemstone luster terms include: metallic (pyrite and hematite), submetallic (sphene and melanite), adamantine, subadamantine, vitreous, changeable, pearly, silky, resinous, greasy, waxy, and dull.

Aquamarine Cabochon with Vitreous Luster
Aquamarine With Vitreous Luster
Shop Aquamarine Gemstones
Adamantine Gemstone Luster

Adamantine luster is typically the most prized luster since it's associated with the high luster of diamond. There are only a handful of gemstones known to exhibit such a high level of luster; examples include zircon, demantoid garnet, and sphene.

Indeed, these gemstones do exhibit an incredible and attractive shine, but there are many gemstones with non-adamantine luster that are just as stunning and often more valuable. For example, the luxurious luster of pearls is beyond compare, as is the greasy luster seen in many varieties of jade.

Oval-Shaped Blue Zircon with Adamantine Luster
Blue Zircon with Adamantine Luster
Shop Blue Zircon
Vitreous Gemstone Luster

Despite the negative connotations with glass, when it comes to luster, glass is more than acceptable. Vitreous luster is described as being glassy or glass-like. Many of the world's most highly-valued gemstones exhibit a vitreous luster, including ruby, sapphire, and emerald. Other gems with vitreous luster happen to be some of the most popular gemstones, such as topaz, beryl, and spinel.

Emerald-Cut Ruby With Vitreous Luster
Ruby With Glass-Like Vitreous Luster
Shop Natural Ruby
Changeable Gemstone Luster

One of the most intriguing forms of luster is a changeable luster. Changeable luster is an altering luster that can be seen in many different types of phenomenal gemstones, including moonstone, cat's eye, ammolite, labradorite, and spectrolite. These phenomenal gems exhibit a different 'changeable' luster depending on how or where they're viewed.

For example, ammolite and labradorite alter luster as they are rotated and tilted back and forth or side to side. Under focused light, cat's eyes and star gemstones display asterisms that appear to glide across the stone as they're turned and tilted, similar to the way light reflects off a string of gleaming silk.

Labradorite with changeable luster
Labradorite with Changeable Luster
Shop Labradorite Gems
Pearly, Silky, Resinous, Greasy, Waxy, and Dull Gemstone Luster

Pearly and silky gemstone luster are quite attractive, perhaps even more so that many vitreous or adamantine gemstones. Gemstones which fall under these luster grades are usually cabochons, although fine materials are sometimes faceted.

Gemstones with pearly luster include those which exhibit iridescence. Some examples include the shimmer seen in fine charoite or rough moonstone, as well as mother of pearl and abalone. Silky luster is often confused with pearly luster, but gems with a silky luster display various forms of simple chatoyancy rather than iridescence. Silky gemstones include tiger's eye and other types of fibrous gems, such as hawks eye, pietersite, malachite, and ulexite.

Sily Charoite With Chatoyant Swirls
Silky and Chatoyant Charoite
Shop Charoite Gems

Gems with waxy luster have a dull shine that appears to be the result of a waxy coating. These include many types of opal and turquoise, as well as flint. Chrysoprase and coral also have a waxy luster, although coral's luster can range from dull to vitreous. Gems with resinous luster appear slightly less glossy and a bit more sticky than those with waxy luster. The best example of a gemstone with a resinous luster would be amber, especially since amber actually is a form of preserved prehistoric resin.

Greasy gemstone luster is just as it sounds; a luster that appears to have an oily or fatty coating. Gemstones with a greasy luster includes nephrite (Hetian seed-jade), jadeite, and peridot. When it comes to dull gemstone luster, there are actually very few materials which exhibit a dull luster; these would include rhodonite or rough turquoise.

Seraphinite: pearly, vitreous, greasy, or dull luster
Seraphinite Can Have Pearly, Vitreous, or Greasy Luster
Shop Seraphinite Gems
Identifying Gems By Luster

Luster can sometimes be used to help to identify gemstone types. To properly inspect the luster of a gemstone, ensure that it’s clean and free from any coating or tarnish. It is best to observe the gem under good lighting at angles which allows light to reflect to and away from the eye.

Since gemstone luster lacks a definite measurement, it is not the most reliable method for identification. However, it can still be helpful if trying to distinguish gems with an adamantine or vitreous luster from those with a greasy or resinous luster.

Featured Gems of the Month

Ruby is July's official birthstone and it's one of the most treasured and valuable gemstones in the world. It's rare to find fine quality Burmese ruby in any shape or size, but round rubies are especially hard to source. We were very fortunate to source many beautiful round-shaped rubies from Burma this month, including large singles, matching pairs, and matching lots.

Red Ruby from Burma
Red Ruby from Burma
Shop For Ruby

Clinohumite is not a gemstone that many peope have even heard of, but for those who have, they know how rare and unusual this fantastic collector's gem truly is. Since there are only three known sources for gem-quality clinohumite (Tajikistan, the Taymyr region in Siberia, and Tanzania) we consider ourselves very lucky to have found such a wonderful rarity.

Faceted Golden Clinohumite
Rare Clinohumite Gemstone
Shop Clinohumite Gems

Hessonite garnet is one of the many awesome gemstone varieties of garnet. More specifically, hessonite belongs to the grossularite family. Other types of grossularite include rare Tsavorite and exotic Mali garnet. In the world of Jyotish or Vedic astrology, hessonite garnet is known as 'Gomed', one of the nine planetary gemstones of Navaratna.

Oval-Shaped Faceted Hessonite Garnet
Hessonite Garnet
Shop Hessonite Garnet
FAQs - Customer Questions

Every month we answer questions of general interest from our customers. Please feel free to send us your questions or suggestions.

Question

I am interested in buying gemstones associated with the seven chakras. Can you let me know which gems are recommended for this and where I can find your selection to view them?

Answer

Based on our own research, gemstones which correspond with the seven centers for chakra energy are as follows:

  • Sahasrara - The Crown: sapphire (yellow or white), citrine, topaz (yellow or white), spodumene (kunzite and hiddenite), white opal, moonstone, iolite, amethyst, tanzanite, and charoite
  • Ajna - The Brow: emerald, jade, tanzanite, charoite, kyanite, and fluorite
  • Vishuddha - The Throat: turquoise, blue topaz, blue zircon, and fluorite
  • Anahata - The Heart: aventurine, emerald, chrysocolla, peridot, jade, rose quartz, kunzite, and morganite
  • Manipura - The Solar Plexus: citrine, sunstone, and tigers eye
  • Swadhisthana - The Sacral: carnelian, citrine, topaz, tigers eye, and spessartite garnet
  • Muladhara - The Root: ruby, hematite, garnet, and smoky quartz
Shop Chakra Gems
Question
Good day! I am from South Africa and want to order from you. Is the ZAR amount the exact amount I have to pay? Plain and simple what do I do to order from you?
Answer
To order from us, you do not have to do anything special. Simply add items to your cart and proceed to our check-out page. Enter in your shipping details and complete your payment via any of our secure methods. Your bank will automatically convert the currency for you. The amount in ZAR (and other currencies) can vary depending on the exchange rate at the time of purchase, but the difference should be very minimal from what was displayed in your shopping cart.
Browse Our Collection

We always welcome your questions, comments and feedback! For those who are interested in attending some gem and jewelry events, please see the details below.

Gem & Jewelry Events for July 2018
Event Name
Location
Venue
Dates
Event Name
International Jewelry Manila 2018
Location
Philippines
Venue
SMX Convention Center Aura, McKinley Parkway, Taguig City, Philippines
Dates
July 5 - 8, 2018
Event Name
Intergem Los Angeles Jewelry Show
Location
USA
Venue
Westin Hotel - Los Angeles Airport, Los Angeles, California, USA
Dates
July 6 - 8, 2018
Event Name
TrendSet Summer 2018
Location
Germany
Venue
New Munich Trade Fair Centre, Messegelande, Germany
Dates
July 7 - 9, 2018
Event Name
JA New York Summer
Location
USA
Venue
Jacob K. Javits Convention Center, New York, NY, USA
Dates
July 15 - 17, 2018
Event Name
InterJeweller 2018
Location
Russia
Venue
Grand Hotel Pearl, Sochi, Russia
Dates
July 18 - 22, 2018
Event Name
Singapore International Jewelry Expo 2018
Location
Singapore
Venue
Marina Bay Sands Expo & Convention Centre, Singapore
Dates
July 26 - 29, 2018
Event Name
The Whole Bead Show
Location
USA
Venue
The Blaisdell Center, Honolulu, Hawaii, USA
Dates
July 27 - 29, 2018

Keep up with our new arrivals before they hit the newsletter by joining our thousands of fans and followers on our social networking pages. We love interacting with our customers - you can visit us on Tumblr, LinkedIn, Twitter, Facebook or Pinterest!

To ensure you can receive our emails, please be sure to add help@gemselect.com to your list of safe contacts or email address book! Please feel free to contact us with any questions, comments, or concerns! We respond to each and every email we receive.

Happy Gem Hunting!
Your friends at GemSelect

  • First Published: February-28-2018
  • Last Updated: July-02-2018
  • © 2005-2019 GemSelect.com all rights reserved.
    Reproduction (text or graphics) without the express written consent of GemSelect.com (SETT Company Ltd.) is strictly prohibited.
More Shapes
Popular Gemstones
  • Sapphire
  • Emerald
  • Ruby
  • Aquamarine
  • Zircon
  • Opal
  • Topaz
  • Tourmaline
  • Garnet
  • Amethyst
  • Citrine
  • Tanzanite
All Gemstones (144)
A B C D E F G H I J K L M N O P Q R S T V Z
  • Actinolite Cat's Eye
  • Agate
  • Agate Geode
  • Almandine Garnet
  • Amazonite
  • Amethyst
  • Ametrine
  • Ammolite
  • Andalusite
  • Andesine Labradorite
  • Apatite
  • Aquamarine
  • Aventurine
  • Beryl
  • Black Opal
  • Bloodstone
  • Boulder Opal
  • Calcite
  • Carnelian
  • Cat's Eye Apatite
  • Cat's Eye Aquamarine
  • Cat's Eye Augite
  • Cat's Eye Gemstones
  • Cat's Eye Moonstone
  • Cat's Eye Opal
  • Cat's Eye Scapolite
  • Chalcedony
  • Charoite
  • Chocolate Opal
  • Chrome Diopside
  • Chrome Tourmaline
  • Chrysoberyl
  • Chrysocolla
  • Chrysoprase
  • Citrine
  • Color-Change Diaspore
  • Color-Change Fluorite
  • Color-Change Garnet
  • Color-Change Sapphire
  • Coral
  • Demantoid Garnet
  • Dendritic Agate
  • Diamond
  • Druzy Amethyst
  • Druzy Azurite
  • Emerald
  • Enstatite
  • Fire Agate
  • Fire Opal
  • Fluorite
  • Fossil Coral
  • Garnet
  • Golden Beryl
  • Grandidierite
  • Grossularite Garnet
  • Hawk's Eye
  • Hematite
  • Hemimorphite Druzy
  • Hessonite Garnet
  • Hiddenite
  • Howlite
  • Idocrase
  • Imperial Topaz
  • Iolite
  • Jade Gemstones
  • Jadeite
  • Jasper
  • Kornerupine
  • Kunzite
  • Kyanite
  • Labradorite
  • Lapis Lazuli
  • Larimar
  • Malachite
  • Malaya Garnet
  • Mali Garnet
  • Maw-Sit-Sit
  • Moonstone
  • Morganite
  • Moss Opal
  • Mother of Pearl
  • Mystic Quartz
  • Mystic Topaz
  • Nuummite
  • Obsidian
  • Opal
  • Opal Doublet
  • Opal in Matrix
  • Pearl
  • Peridot
  • Pietersite
  • Prehnite
  • Pyrite
  • Pyrope Garnet
  • Quartz
  • Quartz Cat's Eye
  • Quartz With Marcasite
  • Rainbow Moonstone
  • Rainbow Pyrite
  • Rhodochrosite
  • Rhodolite Garnet
  • Rhodonite
  • Rose Quartz
  • Rubellite Tourmaline
  • Ruby
  • Ruby in Fuchsite
  • Ruby-Zoisite
  • Rutile Quartz
  • Sapphire
  • Scolecite
  • Seraphinite
  • Serpentine
  • Sillimanite
  • Sillimanite Cat's Eye
  • Smithsonite
  • Smoky Quartz
  • Snowflake Obsidian
  • Sodalite
  • Spectrolite
  • Spessartite Garnet
  • Sphalerite
  • Sphene
  • Spinel
  • Star Diopside
  • Star Garnet
  • Star Gemstones
  • Star Lemon Quartz
  • Star Moonstone
  • Star Rose Quartz
  • Star Ruby
  • Star Sapphire
  • Star Sunstone
  • Strawberry Quartz
  • Sugilite
  • Sunstone
  • Tanzanite
  • Tiger's Eye
  • Tiger's Eye Matrix
  • Topaz
  • Tourmaline
  • Tsavorite Garnet
  • Turquoise
  • Variscite
  • Zircon
Main Categories
  • New Arrivals
  • Gemstone Lots
  • Calibrated Gemstones
  • Gemstones By Piece
  • Top Grade Gems
  • Matching Pairs
  • Cabochon Gemstones
  • Drilled Gems, Briolettes and Beads
  • Birthstones
  • Gemstone Carvings
  • Fancy Gemstones
  • Star Gemstones
  • Unheated Sapphire
English speaking customer support only

Toll Free - USA & Canada only:
1-800-464-1640

International:
+66-39303404

Save Money
No shipping Fees for Additional Items!
$8.90 Worldwide Shipping

Update Translation
 
Current Value
New Value
GemSelect Gemstones
X Close Window
Colored Gemstones
X Close Window
Colored Gemstones
X Close Window
Colored Gemstones
Size and Weight

Gems are always measured in Millimeter (mm)

Dimensions are given as;
length x width x depth,
except for round stones which are;
diameter x depth

Select gems by size, not by weight!
Gem varieties vary in density, so carat weight is not a good indication of size

Note: 1ct = 0.2g

Size Comparison Chart