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Tanzanite Mohs Hardness Scale: Durability? And Daily Wear?
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All About Gemstones

Tanzanite hardness scale

Understanding the Science of Gemstone Hardness

When you hear about the Mohs hardness scale, think of it like a scoreboard where different gemstones show how tough they are. H3: Understanding the Science of Gemstone Hardness

When you hear about the Mohs hardness scale, think of it like a scoreboard where different gemstones show how tough they are. The Mohs scale ranges from 1 to 10, with 1 being super soft like talc (that’s the stuff in baby powder!) and 10 being super hard like a diamond – nothing can scratch it! This hardness rating is a key measure of a mineral’s resistance to scratching, essentially rating the mineral hardness.

On this scale, each higher number can scratch all the ones below it. So, if you’re a gemstone sitting at number 7, like quartz, you can scratch all those ranked 1 to 6, but accompany them with caution because minerals with higher ranks—like sapphire, which boasts a hardness rating of 9 on the scale—can certainly leave a mark.

Here’s a full list of gemstones and their Mohs hardness scale:

Diamond10Hypersthene5 – 6
Synth. MoissanitIlmenite5 – 6
Ruby9Lapis Lazuli5 – 6
Sapphire9Lazulite5 – 6
AlexandriteNepheline5 – 6
ChrysoberyllNeptunite5 – 6
HoltitePargasite5 – 6
YAGRichterite5 – 6
ZirconiaSamarskite5 – 6
Rhodizite8 – 8½Stibiotantalite5 – 6
Taafeite8 – 8½Tremolite5 – 6
Spinel8Turquoise5 – 6
Topaz8Analcime5 – 5½
Aquamarine7½ – 8Datolite5 – 5½
Red Beryl7½ – 8Durangite5 – 5½
Precious Beryl7½ – 8Eudialyte5 – 5½
Gahnite7½ – 8Goethite5 – 5½
Galaxite7½ – 8Herderite5 – 5½
Painite7½ – 8Hydroxylherderite5 – 5½
Phenakite7½ – 8Meliphanite5 – 5½
Emerald7½ – 8Mesolite5 – 5½
AndalusiteMicrolite5 – 5½
EuclaseMonazite5 – 5½
HambergiteNatrolite5 – 5½
SapphirineNickeline5 – 5½
Dumortierite7 – 8½Papagoite5 – 5½
Almandine7 – 7½Psilomelane5 – 5½
Boracite7 – 7½Scolecite5 – 5½
Cordierite7 – 7½Sellaite5 – 5½
Danburite7 – 7½Thomsonite5 – 5½
Grandidierite7 – 7½Titanite5 – 5½
Pyrope7 – 7½Wolframite5 – 5½
Schorlomite7 – 7½Yttrotantalite5 – 5½
Sekaninaite7 – 7½Apatite5
Simpsonite7 – 7½Bismutotantalite5
Spessartine7 – 7½Childrenite5
Staurolite7 – 7½Chlorapatite5
Turmaline7 – 7½Dioptase5
Uvarovite7 – 7½Eosphorite5
Rock Crystal7Hydroxylapatite5
Smoky Quartz7Strass5
Garnet6½ – 7½Ekanite4½ – 6½
Jeremejevite6½ – 7½Apophyllite4½ – 5
Sillimanite6½ – 7½Augelite4½ – 5
Zircon6½ – 7½Charoite4½ – 5
Axinite6½ – 7Gaspéite4½ – 5
Chalcedony6½ – 7Hodgkinsonite4½ – 5
Chrysoprase6½ – 7Legrandite4½ – 5
Diaspore6½ – 7Pectolite4½ – 5
Ferro-Axinite6½ – 7Scheelite4½ – 5
Gadolinite6½ – 7Wardite4½ – 5
Grossular6½ – 7Wollastonite4½ – 5
Hiddenite6½ – 7Bayldonite
Jadeite6½ – 7Colemanite
Jasper6½ – 7Parisite
Kornerupine6½ – 7Prosopite
Kunzite6½ – 7Yugawaralite
Mangan-Axinite6½ – 7Kyanite4 – 7
Peridot6½ – 7Sérandite4 – 5½
Pollucite6½ – 7Chabazite4 – 5
Serendibite6½ – 7Friedelite4 – 5
Sinhalite6½ – 7Lithiophilite4 – 5
Spodumene6½ – 7Mordenite4 – 5
Tanzanite6½ – 7Triphylite4 – 5
Thorianite6½ – 7Variscite4 – 5
Tinzenite6½ – 7Zincite4 – 5
GGGCarletonite4 – 4½
Magnesio-AxiniteHübnerite4 – 4½
NambulitePurpurite4 – 4½
Cassiterite6 – 7Ammonite4
Clinozoisite6 – 7Barytocalcite4
Epidote6 – 7Flourite4
Hancockite6 – 7Leucophanite4
Pyrolusite6 – 7Libethenite4
Sogdianite6 – 7Rhodochrosite4
Amazonite6 – 6½Magnesite3½ – 4½
Andesine6 – 6½Siderite3½ – 4½
Anorthoclase6 – 6½Ankerite3½ – 4
Benitoite6 – 6½Aragonite3½ – 4
Bixbyite6 – 6½Azurite3½ – 4
Bytownite6 – 6½Chalcopyrite3½ – 4
Chondroite6 – 6½Creedite3½ – 4
Helvite6 – 6½Cuprite3½ – 4
Hyalophane6 – 6½Dickinsonite3½ – 4
Labradorite6 – 6½Dolomite3½ – 4
Marcasite6 – 6½Euchroite3½ – 4
Microcline6 – 6½Langbeinite3½ – 4
Nephrite6 – 6½Malachite3½ – 4
Norbergite6 – 6½Mimetite3½ – 4
Oligoclase6 – 6½Pentlandite3½ – 4
Petalite6 – 6½Powellite3½ – 4
Prehnite6 – 6½Scorodite3½ – 4
Pyrite6 – 6½Shungite3½ – 4
Rutile6 – 6½Shattuckite3½ – 4
Sanidine6 – 6½Sphalerite3½ – 4
Smaragdite6 – 6½Wavellite3½ – 4
Sugilite6 – 6½Wurtzite3½ – 4
Tantalite6 – 6½Adamite
Xonotlite6 – 6½Anhydrite
Zoisite6 – 6½Chiolite
Hurlbutite6Cacoxenite3 -4
Lawsonite6Coral3 -4
Pumpellyite6Ludlamite3 -4
Tephroite6Anglesite3 – 3½
Vlasovite6Baryte3 – 3½
Zektzerite6Boleite3 – 3½
Hematite5½ – 6½Cerussite3 – 3½
Hedenbergite5½ – 6½Celestine3 – 3½
Magnetite5½ – 6½Descloizite3 – 3½
Manganotantalite5½ – 6½Greenockite3 – 3½
Opal5½ – 6½Howlite3 – 3½
Rhodonite5½ – 6½Millerite3 – 3½
Actinolite5½ – 6Phosphophyllite3 – 3½
Allanite5½ – 6Witherite3 – 3½
Anatase5½ – 6Bornite3
Beryllonite5½ – 6Calcite3
Brookite5½ – 6Kurnakovite3
Bustamite5½ – 6Shortite3
Canasite5½ – 6Wulfenite3
Cobaltite5½ – 6Serpentine2½ – 5½
Euxenite5½ – 6Pearl2½ – 4½
Fabulite5½ – 6Jet2½ – 4
Fergusonite5½ – 6Chalcocite2½ – 3
Haüyne5½ – 6Crocoite2½ – 3
Leucite5½ – 6Gaylussite2½ – 3
Marialite5½ – 6Gold2½ – 3
Meionite5½ – 6Inderite2½ – 3
Milarite5½ – 6Lepidolite2½ – 3
Montebrasite5½ – 6Pyrargyrite2½ – 3
Natromontebrasite5½ – 6Silver2½ – 3
Periclase5½ – 6Stolzite2½ – 3
Pyroxmangite5½ – 6Vanadinite2½ – 3
Sarcolite5½ – 6Whewellite2½ – 3
Scorzalite5½ – 6Brucite
Scapolite5½ – 6Cryolite
Sodalite5½ – 6Linarite
Tugtupite5½ – 6Lizardite
ChromiteChrysocolla2 – 4
EnstatiteClinochrysotile2 -3
LinobateFuchsite2 -3
MagnesiochromiteMuscovite2 -3
MoldavitePhosgenite2 -3
WillemiteShomiokite2 -3
Aeschynite5 – 6Amber2 – 2½
Bronzite5 – 6Cinnabar2 – 2½
Cancrinite5 – 6Ettringite2 – 2½
Catapleiite5 – 6Kämmererite2 – 2½
Ceruléite5 – 6Mellite2 – 2½
Clinoenstatite5 – 6Senarmontite2 – 2½
Davidite5 – 6Ulexite2 – 2½
Diopside5 – 6Villiaumite2 – 2½
Ferrosilite5 – 6Gypsum2
Hornblende5 – 6Stichtite1½ – 2½
Sulphur1½ – 2½
Covellite1½ – 2
Melonite1½ – 2
Realgar1½ – 2
Vivianite1½ – 2
Palygorskite1 – 2
Pyrophyllite1 – 2

Positioning Tanzanite on the Mohs Scale

Tanzanite is like that new kid on the block in the world of gemstones. Emerging from the rich foothills of Mount Kilimanjaro in Tanzania, these gemstones boast a cool violet-blue color that really sets them apart.

Now, if we delve into where tanzanite fits on the Mohs hardness scale, it’s akin to glass or steel, ranking at a 6 to 7.

This position signifies reasonable durability but doesn’t quite rival the unparalleled hardness of a diamond.

While tanzanite is more resilient than delicate materials like pearls, indicating its suitability for various types of adornments, its unique luster and color require conscientious care, particularly in high-contact items like rings that are subject to frequent wear.

Tanzanite’s Hardness

Tanzanite, a true spectacle within the realm of gemstones, has a Mohs hardness of 6 to 7. This fascinating gem mineral exhibits durability that places it between orthoclase and quartz in terms of hardness, making it moderately resistant to scratches and daily wear. Here’s the adjusted table including tanzanite:

Mohs HardnessGemstone
9Corundum (Ruby/Sapphire)

The Durability of Tanzanite in Jewelry

Daily Wear and Tear: Is Tanzanite Up To The Challenge?

Tanzanite is kind of like your favorite pair of jeans. It’s cool, with its vibrant blue-violet shine, as birthstone for December, it’s fashionable and something you’re drawn to wear frequently. However, similar to how denim can fray and stretch, tanzanite is susceptible to scratches due to its softer nature among jewelry stones.

Although tanzanite can indeed complement your everyday style, its placement among jewelry pieces can influence its longevity.

Think about it: you’re waving your hands around, maybe bumping into things, and if you’re wearing a tanzanite ring, it’s exposed and more prone to scratching.

Over time, without proper care, it might lose some of its original luster. That’s why, while it may seem like a suitable choice for an everyday ring, tanzanite’s beauty is best preserved in jewelry forms that suffer less impact—like pendants or earrings—which maintain their condition over the years.

Remember, being gentle with your shiny blue friend will go a long way toward preventing any sort of scratching. Oh, and tell your local jeweler to handle it with care—no extreme temperatures when cleaning this delicate gem!

Synthetic options might offer more durability if you’re tough on your jewelry. Occasionally take your tanzanite pieces to a trusted jewelry expert for professional maintenance, especially if they’re custom crafts from a jewelry-making kit.

Care Tips for Preserving Tanzanite’s Integrity

Taking care of tanzanite isn’t a big deal, it’s sort of like caring for a pet. You just need to know what it likes and doesn’t like. When it comes to ensuring the longevity and sparkle of your favorite pieces, here’s how you can maintain your tanzanite jewelry’s splendor:

  1. Avoid Bumps and Scrapes: Remember, it’s not the strongest stone. Tanzanite can develop fractures if it’s knocked hard. When you’re out playing sports or engaging in activities that could lead to accidental whacks, it’s wiser to keep your tanzanite treasures safely stored away.
  2. Watch Out for Chemicals: Harsh chemicals are a threat to tanzanite’s vibrancy. Chlorine in pools or abrasive cleaning products can dull its sparkle and even cause damage. It’s best to remove your tanzanite jewelry before swimming or cleaning.
  3. Keep it Comfy: Tanzanite prefers stability. Abrupt temperature changes can be harmful, so avoid exposing your tanzanite pieces to extreme heat or cold, preserving their structure and natural softness.
  4. Safe and Cozy Storage: After wearing, gently rinse your tanzanite with water and dry it with a soft cloth before storing. Provide a secluded compartment or a padded jewelry box where it won’t come into contact with other items that could scratch it.
  5. Spa Day: When home care is needed, opt for a steam cleaner cautiously or a gentle hand wash with mild soapy water using a soft brush to dust the surface, enhancing the stones’ shine without risking any damage.

It’s really quite simple! By following these straightforward care tips, your tanzanite will continue to dazzle. And remember, for a thorough refresh or if you encounter any uncertainties, a professional jeweler’s expertise—considering options like ultrasonic or steam cleaning for sapphire, which is less susceptible to heat and chemicals—can provide the perfect spa treatment for your cherished jewelry.

Comparing Tanzanite to Other Gemstones

How Tanzanite Stands Against Diamonds, Sapphires, and Rubies

Okay, let’s put tanzanite in the ring with some of the big name gemstones—diamonds, sapphires, and rubies. When it comes to toughness, diamonds are the champs.

They’re a perfect 10 on the Mohs scale, so they can take a lot of knocks and still look awesome. Sapphires and rubies are like the runners-up; they score a mighty 9, which means they’re super strong too.

Now, tanzanite? It’s more of the underdog in tanzanite mining, but it harvests a prize worth boasting about—a brilliant color gemstone known for its remarkable blue-purple hues.

With a score between 6 to 7 on the Mohs scale, it needs to be treated more like a fine piece of art. It’s not as hard as diamonds, sapphires, or rubies, but here’s the cool part: tanzanite’s color is super unique—a blue that can shift to violet depending on the light.

And while it’s a bit softer, it can still be part of your jewelry collection if you take care of it.

A skilled cutter can really bring out tanzanite’s vibrant colors, making it compete with the sparkle and elegance of these other precious stones.

So, when you’re choosing, think about how often you’ll wear it and what adventures you’ll bring it on. Tanzanite might need a little more TLC, but it brings its own distinct and captivating sparkle to the show!

GemstoneMohs HardnessColorLusterCrystal SystemHighlight of Qualities
Tanzanite6.5 – 7Blue to violetVitreousOrthorhombicRare, found only in Tanzania, often heat-treated for enhanced color
Diamond10Colorless, can be blue, yellow, pink, etc.AdamantineCubic (Isometric)Hardest natural material, excellent brilliance, widely used in jewelry and industrial applications
Sapphire9Typically blue, can be yellow, pink, greenVitreousTrigonal (Hexagonal)Corundum variety, known for its durability and vivid colors, often heat-treated
Ruby9RedVitreousTrigonal (Hexagonal)Corundum variety, prized for its deep red color, high durability, often heat-treated

Making an Informed Choice with Tanzanite’s Hardness in Mind

When you’re getting yourself a gemstone, it’s like picking out a new phone. You want something cool, but you also need to make sure it fits your life. With tanzanite, remember, it’s kind of in the middle for hardness. Not too soft, but not the kind of hard you’d take to battle.

So, you gotta ask yourself, “How will I wear this?” If you’re like, “I want to show it off every day!” then think about a safe setting that keeps it snug, like bezel or halo settings. But if it’s for special days, like a fancy party or a big date, then maybe you can go with something more delicate.

Just know this: A little know-how goes a long way. By knowing tanzanite’s perks and quirks, you can make a choice that’s awesome for you and keep your gem looking gorgeous.

Addressing Common Concerns About Tanzanite

Can Tanzanite Crack Easily?

You might worry that tanzanite will crack if you just look at it wrong, but that’s not totally true. Sure, when discussing fractures, tanzanite can be somewhat more susceptible due to its molecular structure.

However, it’s generally not going to crack under normal conditions. Think of it like ice cream – it’s solid and keeps its shape, but if you poke it with something sharp or hit it too hard, you’ll likely see a dent or a crack.

It can handle the day-to-day wear, but rapid temperature changes are a no-go. If tanzanite experiences extreme temperature fluctuations in a short period, it’s at risk of stress fractures. Additionally, tanzanite’s perfect clarity gemstone attribute lends it a unique cleavage that can be a vulnerability point. A direct hit there could cause trouble.

Bottom line: Treat your tanzanite jewelry nicely. No steam cleaning and be careful with bumps and knocks to preserve its captivating clarity and prevent any possible fractures.

Does Exposure to Sunlight Affect Tanzanite’s Color Longevity?

Sunshine is great for beach days but not so much for tanzanite’s color. The truth is, Tanzanite enjoys cooler, sheltered environments; prolonged exposure to strong sunlight can impact its stunning blue-violet hue—a phenomenon known as tanzanite change.

The color gemstone’s unique beauty might start to wane, potentially diminishing the vibrancy that first captured your admiration.

But don’t panic! It’s not as if your tanzanite accessory will immediately become translucent with a brief jaunt outdoors.

The color shift we’re discussing requires consistent, extensive sun exposure over an extended period.

Therefore, indulging in your daily ventures outdoors, such as a leisurely walk or picking up a favorite smoothie, won’t endanger your beloved gem.

Nonetheless, it’s wise to treat tanzanite as you would your own skin; although it doesn’t require SPF protection, it does need respite from potent ultraviolet rays.

By providing periodic rest in milder conditions, your tanzanite stone will maintain its enchanting luster for the long haul. Just ensure to keep it away from extreme heat changes to preserve its surface condition.

FAQ About Tanzanite and Mohs Hardness

What precautions should I take when wearing Tanzanite every day?

Wearing tanzanite every day? Cool! Just remember, while tanzanite jewelry, such as engagement rings and pendants, can certainly be worn daily, it’s best to safeguard it from hard knocks.

Ensure your wedding or engagement ring is removed during high-impact chores or while engaging in sports to prevent scratches that can mar its beauty.

A soft cloth and mild soapy water will suffice for periodic cleaning and to retain its luster.

Given that tanzanite is a bit more delicate, pampering your precious gemstone with extra care will keep it sparkling for years to come.

If Tanzanite is not the hardest gemstone, why choose it for jewelry?

Tanzanite may not be a tough cookie, but its beauty is off the charts! Exuding elegant blue-violet hues, tanzanite brings a unique flair to jewelry design that captivates with its rarity and dazzling color palette.

Found exclusively in the Merelani Hills of Tanzania, this gem complements any wardrobe with a sophisticated touch that is both luxurious and playful. By choosing tanzanite, you’re not just wearing a gem—you’re making a bold statement with a piece that is as distinctive as it is enchanting.

How does the Mohs hardness of Tanzanite influence its value?

The Mohs hardness of tanzanite is kinda like a gemstone’s game plan—it tells jewelers how to handle it. The Mohs hardness of Tanzanite, sitting at 6.5 to 7, impacts its durability but isn’t the sole factor in determining its value.

Indeed, value assessments often involve consultation with the Gemological Institute of America, which considers the interplay of tanzanite’s carat weight alongside color and clarity. But when it comes to value, hardness isn’t the boss.

Tanzanite scores big on its vibrant color, rarity, and the single-source provenance of Tanzania. Even though it’s medium-hard, tanzanite still wins hearts and keeps its value strong because of its unique beauty and the tender loving care it receives from both jewelers and collectors.

Is Tanzanite a soft Stone?

Yep, tanzanite isn’t the hardest rock at the party—it’s somewhere in the middle. Ranking a 6.5 to 7 on the Mohs hardness scale, it’s not as soft as talc, which defines the base of mineral hardness, but it’s also not as tough as a diamond, the reigning champion with a perfect score of 10.

So, you’ve got to treat it a bit carefully, like a cool collectible toy or your favorite book. Keep it safe from scratches and bumps, and tanzanite will stay your shiny friend for a long time, boasting not only an adequate level of durability but also a clarity that is generally quite clean, which enhances its desirability among gemstone connoisseurs.

Tanzanite Hardness vs Diamond?

When tanzanite and diamond step into the ring, the diamond is the heavyweight champ. Diamonds are the hardest known mineral to us, scoring a perfect 10 out of 10.

They can take on pretty much anything. Tanzanite, on the other hand, is more of a lightweight, with a score between 6 to 7. It’s still strong enough for jewelry, but next to diamond, it needs a little more care to stay scratch-free.

Mohs Hardness6.5 – 710None
ColorPrimarily blue to violetColorless, can be blue, yellow, pink, etc.Blue (both can be blue)
Crystal SystemOrthorhombicCubic (Isometric)None
Refractive Index1.685 – 1.7072.417 – 2.419None
Specific Gravity3.353.52Close
LusterVitreousAdamantineHigh luster (both have high luster)
Dispersion0.0280.044Both exhibit dispersion, but diamond has higher
ToughnessFair to poor (prone to cleavage)ExcellentNone
RarityRare (found only in Tanzania)Rare but more widely distributedBoth are rare
Primary UseJewelryJewelry, industrial applicationsJewelry
Heat SensitivitySensitive (can change color with heat)Not sensitiveNone
TreatmentOften heat-treated to enhance colorUsually untreated (color can be treated)Both can be treated for color enhancement
Market ValueHigh, but generally less than diamondVery high, one of the most expensiveBoth have high market values

This table shows the key differences and similarities between tanzanite and diamonds.


So there you have it! Tanzanite is one of those gemstones that isn’t just about being tough, it’s about being beautiful. Its unique blue-violet color makes it super special.

Yes, it’s not as hard as a diamond, so it’s not the best for rough-and-tumble wear, but with the right care and the right setting, it can totally be part of your everyday bling. Just treat it nicely, and your tanzanite will keep turning heads for years to come.

Kind regards,

Edwin van Vliet

Picture of Edwin van Vliet

Edwin van Vliet

Edwin van Vliet is a seasoned life coach with an unwavering passion for the transformative potential of crystals and gemstones in healing. At 43 years old, and with his 16 years of experience, Edwin's journey to becoming a life coach was marked by his own personal healing experiences. Through extensive therapy and the supportive energy of crystals, he not only discovered his true potential but also found a deep passion for guiding others on their paths to self-discovery.

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