Diamonds are the classic gemstone, beloved for their unbeatable hardness, stunning sparkle, unique formation, and symbolism in everlasting love. White diamonds are the standard for engagement rings, so everyone should acquire a good base knowledge before they buy diamonds.
Although white is standard, you can find natural diamonds for sale in 12 base hues, including pink, yellow, blue, purple, black, and more. Diamonds aren’t as rare as you might think, but rarer types like a natural red diamond will be pricier.
Our diamond auction options are perfect gifts, especially as April birthstones and 60th wedding anniversary gemstones.
FAQs
What are the four types of diamonds?
Various categories exist for diamonds, but the four types of diamonds for sale you’ll often see are:
1. Type Ia: Yellowish hue from nitrogen impurities clustered throughout the crystal
2. Type Ib: Rare type with scattered nitrogen clusters causing intense yellow, orange, brown, or yellow-green coloring
3. Type IIa: Rarest (1%), priciest type; No nitrogen impurities, incredible sparkle
4. Type IIb: Rare type; No nitrogen impurities but boron impurities present, making them electrically conductive and blue or blue-gray in undertone
What is the difference between natural and lab-grown diamonds?
The main differences between natural and lab-grown diamonds for sale is how much they cost and how they were created. You’ll see higher prices when you buy natural diamonds given their rarity and reputation.
Natural diamonds form deep underground from high pressure and temperatures. Lab-grown diamonds are made by humans in a controlled lab environment but end up with the same properties and structure.
How is the price of a diamond determined?
The price of white diamonds for sale, the most popular type, is based on the 4 C’s of diamond grading which is standardized by GIA:
> Color: Graded from D to Z; D-F is colorless and most valuable, G-J is near colorless, K-M is faint color, N-R is very light color, and S-Z has a light yellow, gray, or brownish undertone
> Cut: Arguably the most important factor, as it enhances brilliance, fire, and scintillation; Graded from Excellent to Poor, with 0.1% getting Excellent while 90% get Fair or Poor
> Clarity: Measure of inclusions, graded on a scale from the most valuable FL (flawless) to least valuable I (included); Most fall under VS (very slightly included) to SI (slightly included)
> Carat Weight: Weight equal to 0.2 grams, measured precisely as price-per-carat can dramatically change with larger sizes
Note: The S-Z color grade is too light to be a fancy-colored diamond. Color grading for fancy-colored diamonds is based on the hue’s rarity, intensity, and tone.
Which diamond cut sparkles the most?
Round brilliant is the winner for sparkle, making it the most popular cut. But you can buy diamonds with princess, radiant, cushion, or oval cuts to turn heads with stunning sparkles and color flashes.
What size diamond is the best value?
Most diamond engagement rings have a 1-carat or 1.5-carat diamond, but everyone is different. We recommend looking for a 0.5- to 0.7-carat diamond auction listing, which can have great quality while still fitting a $1,000 to $2,000 budget. Check out diamonds for sale under 0.5 carats if your budget is under $1,000.
How do I choose the right diamond for me?
When you’re buying diamonds, first decide what shape you like. Round or princess is classic, but cushion or radiant may fit your style better. Next, figure out your ideal carat weight — your finger size and ring setting may play a role.
Then, determine your budget and consider slightly lower grades of clarity, color, and cut if you need to compromise. Still over budget? Consider going down in carat weight just a little, as even a 10% difference can knock down the price when you buy diamonds.
What types of diamonds are available for sale?
We have hundreds of diamonds for sale for every style and budget. You can find diamond auctions with VVS to I clarity, standard round to unique hexagon cuts, white and fancy colors, heated or untreated, and more.
Are the diamonds for sale on Gem Rock Auctions certified?
We encourage our sellers to include reputable lab certificates from agencies like GIA, IGI, AIG, or HRD for all diamond auction listings. In the sidebar above, you can even filter by lab certificate agency.
Why should I buy diamonds at an auction?
The biggest advantage of diamond auctions: great deals. An online diamond auction saves you the added price of retail markups while allowing you to support small businesses and explore a wider range of diamonds for sale from around the world.
Of course, you need to trust who you buy diamonds from. We rigorously vet every seller through our Verified Sellers program and they must follow a strict code of conduct. If you’re unsure about any diamond auction listing, you can request a free audit from a third-party expert panel through our Gemstone Sheriff program.
Further Reading
Opals
Gemstones
Jewelry
Coins
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