Sapphire
Available in blue and many other colors. Strong durability makes it a practical center stone.
Gemstone Guide
Gemstones are judged by more than a name or carat weight. Color, transparency, cut, dimensions, durability, origin, and disclosed treatments all shape how a stone looks and how it should be worn.
How gemstone quality is described
- Color: hue, tone, saturation, and evenness. The most desirable balance varies by species and personal preference.
- Clarity and transparency: some gems are prized for transparency, while others normally contain visible inclusions. Inclusions can identify natural formation, but fractures near edges or corners may affect durability.
- Cut: proportions and polish influence brightness, color distribution, symmetry, and face-up size.
- Dimensions and weight: gemstone densities differ, so equal-carat stones may have very different sizes. Compare millimeters.
Durability and everyday wear
The Mohs scale measures scratch resistance, not resistance to chipping or breaking. Setting protection, cleavage, toughness, and daily habits matter too.
| Gemstone | Mohs hardness | Wear guidance |
|---|---|---|
| Diamond | 10 | Excellent scratch resistance; can still chip at vulnerable edges. |
| Sapphire and ruby | 9 | Well suited to frequent wear with normal care. |
| Topaz | 8 | Scratch resistant but can cleave; avoid sharp impacts. |
| Emerald | 7.5–8 | Often included and treated; protect from impact, heat, and harsh cleaning. |
| Amethyst and citrine | 7 | Good for jewelry; avoid abrasion and prolonged strong light or heat. |
| Opal | 5.5–6.5 | More delicate; avoid drying, impact, heat, and ultrasonic cleaning. |
| Pearl | 2.5–4.5 | Soft organic gem; keep away from perfume, cosmetics, and abrasion. |
Popular gemstones at a glance
Ruby
Red corundum valued for saturated color. Fine stones commonly include natural characteristics.
Emerald
Known for green color and characteristic inclusions. Many are clarity enhanced and require gentler care.
Aquamarine
A blue-to-green beryl that often has good clarity; protect it from hard knocks.
Opal
Valued for play-of-color. Its water content and relative softness call for careful wear and storage.
Pearl
An organic gem evaluated by luster, surface, shape, color, size, and matching.
Natural, lab-created, and treated stones
“Natural” describes geological origin; it does not mean untreated. Heat, oil or resin filling, irradiation, diffusion, and other treatments may change appearance or durability. Lab-created stones share key chemical and optical properties with their natural counterparts but have a different origin. Imitations only resemble another gem. Product information should state material, origin when known, and relevant treatment disclosures.
Choose for your lifestyle
For a ring worn daily, prioritize durability and a protective setting. Earrings and pendants receive less impact and can accommodate more delicate stones. Remove gemstone jewelry before exercise, swimming, housework, or using chemicals. Store pieces separately and follow care instructions for the least durable material in the piece.
Ask Crown Jewelry about a gemstone's dimensions, origin, treatment, or care before ordering.