Everything you need to know about choosing, evaluating, and understanding precious gemstones
The "Four Cs" are the universal criteria used by gemologists and collectors worldwide to evaluate the quality and value of colored gemstones.
The most important factor for colored gemstones. Color is evaluated by three components:
Refers to the presence of inclusions (internal) and blemishes (external). Colored stones are graded differently from diamonds:
The quality of cut determines how well the stone reflects light and displays its color. Key factors include:
Weight is measured in carats (1 carat = 0.2 grams). Larger stones are exponentially rarer:
Expert Tip: For colored gemstones, color is king. A well-saturated stone with minor inclusions will almost always be more valuable than a perfectly clean stone with pale color. Always prioritize vivid, saturated color when making your choice.
The cut shape affects how a gemstone interacts with light and reveals its color. Each shape has its own character.
Maximum sparkle, 57 facets
Step-cut, elegant clarity
Elongated brilliance
Soft corners, vintage feel
Teardrop, dramatic look
Triangular, bold fire
Boat-shaped, looks larger
Romantic, rare in gems
Square step-cut, art deco
Domed, no facets, smooth
Click on any gemstone to explore its characteristics, origins, and what to look for when buying.
The most prized of the beryl family. Colombian emeralds command the highest prices for their warm, vivid green. Minor oil treatment is standard and accepted in the trade.
Browse Emeralds →"Pigeon Blood" Burmese rubies are the most valuable colored gemstones in the world. Second hardest natural gem after diamond. Untreated specimens command extraordinary premiums.
Browse Rubies →Kashmir sapphires are the gold standard — velvety blue with a soft, luminous quality. Sapphires come in every color except red (which would be ruby). Padparadscha is the rarest fancy sapphire.
Browse Sapphires →Historically confused with ruby, spinel is now recognized as a prized gem in its own right. Never treated — all color is natural. The "Black Prince's Ruby" in the British Crown is actually a spinel.
Browse Spinels →The "neon" gemstone. Copper content gives Paraiba its unmistakable electric glow. Brazilian specimens from the original Paraiba mine are the most valuable colored gems per carat after rubies.
Browse Tourmalines →"Emerald by day, ruby by night." One of the rarest gemstones in existence. Strong color change specimens from Russia command the highest prices. A true collector's stone.
Browse Alexandrites →The pink variety of beryl (same family as emerald). Its warm, romantic tones make it extremely popular for engagement rings. Large clean specimens are relatively affordable compared to other precious gems.
Browse Morganites →Found in only one place on Earth — near Mount Kilimanjaro. Geologists estimate the supply may be exhausted within 20–30 years, making it a potential investment gem. Strong trichroism shows blue, violet, and burgundy.
Browse Tanzanites →Hardness determines a gemstone's durability for everyday wear. Higher number = more scratch-resistant.
Practical Tip: For engagement rings and jewelry worn daily, choose gemstones with hardness 7 or above. Stones below 7 (like tanzanite, opal) are better suited for earrings and pendants where they'll receive less impact.
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