How to Identify a Raw Diamond (Easy Explained!)

How to Identify a Raw Diamond

Do you know how to identify a raw diamond? Well, you are at the perfect place to find the answer to such a question.

A raw diamond does not look like the polished gemstone you’re used to seeing. You can identify a raw diamond through a few different methods. You’ll consider the gravity of it. You can test the hardness of the stone. You can use ultraviolet light, as well as test for the stone’s thermal absorption level.

Here are 6 methods how to identify a raw diamond:

1. Test for Gravity

2. Test for Hardness

3. Use Ultraviolet Light

4. Test by Thermal Absorption

5. Try the Fog Test

6. Test with Heat

Read on to find out how to tell if you’ve found a raw diamond and facts about them you should know.


What Does a Raw Diamond Look Like?

Raw diamonds look quite different than polished gemstones you see on jewelry. They look like translucent stones in some cases and pieces of glass in others.

They also grow to different sizes depending on how long ago they began forming. 

A raw diamond hasn’t been altered at all, other than being mined from the ground. They’re not polished or cut.

They often have a yellowish or brown tint to them.

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How Do You Identify a Raw Diamond if You Think You’ve Found One?

You have a few options for how you can try to identify the stone you’ve found as a raw diamond. Keep reading this section to find out what they are.

1. Test for Gravity

Diamonds have higher densities than other gemstones. They also have a high enough density to sink in water. You can filter out a real diamond by testing for its gravity.

All you need is a regular drinking glass. Fill it with water up to about the 3/4 mark. Drop your stone in the glass full of water.

You’re looking for it to sink or float. If it floats, it’s not a diamond. If it sinks, you’ve likely found a real raw diamond.

2. Test for Hardness

Diamonds are known for being the hardest gemstones on the Mohs scale. Mohs scale gives a rating for hardness levels of stones.

Diamonds are virtually scratch resistant, which is one reason they’re used in engagement rings. “Diamonds Are Forever” is a saying that holds true for this reason.

Diamonds will scratch other minerals that are positioned lower than them on the Mohs scale. The level right below a diamond is corundum.

Corundum is a stone category that includes sapphires and rubies. You can try scratching corundum with your suspected raw diamond and if it can do it, it’s likely genuine.

You’ll have to be cautious, though. There are some metals that may be softer than diamond but are scratch-resistant for other reasons.

That means you don’t want to rely solely on the hardness test to determine if you’ve found a raw diamond.

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3. Use Ultraviolet Light

Some diamonds glow blue when put under an ultraviolet light. The problem lies in that it is only some of them. You’ll also see shades of red, orange, or yellow sometimes.

It doesn’t mean you shouldn’t try using the ultraviolet light test, it just means you shouldn’t rely solely on this test, either.

4. Test by Thermal Absorption

This is the best test you can do. You want to see if the stone absorbs heat quickly. Diamonds have a high rate of thermal absorption. The trick is, how do you test for this?

There’s a device known as a diamond tester. There is a small metal head on the end of the tester that touches the stone in question. The metal head produces a quick spurt of heat and measures how fast the stone absorbs it. That information is used to determine that it’s a raw diamond or not.

You could buy one of these for yourself. However, that’s not necessary. Every worthy jeweler will have at least one diamond tester.

You can visit a jewelry store and ask a salesperson or jeweler to test your stone. 

5. Try the Fog Test

A fog test is easy. You don’t need anything extra to do a fog test. All you’ll do is hold the stone in front of your mouth.

Then, breathe on it. You should see fog collect in and on the stone immediately. If it disappears quickly, it’s more likely the stone is a raw diamond. 

6. Test with Heat

Diamonds are formed when carbon is exposed to extreme heat and compression over billions of years. That makes diamonds durable when exposed to heat after mining. 

This test requires a lighter, pliers, a glass of cool water, and fireproof gloves for protection. Hold the diamond with the pliers.

Bring the lighter’s flame to the diamond and heat it for around 45 seconds. Then, drop the stone into the cool water in the glass. 

If the stone doesn’t have a reaction, it may be a raw diamond. If it shatters, it is not. Glass and softer stones will break into pieces because of the extreme temperature changes. Diamond will not.

How to check rough diamonds at home >> Check out the video below:

More Tests Are Better Than One

You shouldn’t do just one test and decide you’ve found a genuine raw diamond. It’s best to confirm your suspicions through multiple tests.

The more confirmation you can get that you’ve found a true raw diamond, the better. Some of the tests we mentioned above are not full proof.

But if you couple the results of one test with results of other tests that are pointing to a real raw diamond, it’s more likely that you’re correct.

Once you feel you’ve come to a positive conclusion, it’s best to take your raw diamond to an expert jeweler to have it confirmed professionally.

Then you can start to get an idea of the value of what you’ve found. 

How Do Raw Diamonds Form?

Diamonds are quite simple in their formulation if you think about it. All you need to make a diamond is pressure, carbon, and heat. That’s it.

There’s nothing fancy about it. However, these three ingredients have to come together in just the right way to create a raw diamond.

Carbon is a naturally occurring element that’s part of everything. It’s in the air, the ocean, and even your body. The carbon in the Earth’s crust is what diamonds are made of.

Carbon in the crust, specifically in the mantle layer, is exposed to extreme heat and intense pressure. The mantle sits right above the core of the Earth. The core is where the molten metals are. 

When the carbon atoms heat up so much, they begin to fuse together. The pressure at the depth of the mantle is such that the carbon bonds are unbreakable.

Slowly, the bonded atoms begin to grow into crystals. The crystals continue to grow until volcanic activity takes them closer to the surface.

How Long Do Diamonds Take to Form?

Genuine raw diamonds made in the Earth’s mantle take an extremely long time to form. Just how long is it? Naturally occurring diamonds have been bonding and growing for at least 1 billion years.

Some of them have taken up to 3.3 billion years. 

Unlike natural raw diamonds, lab-grown diamonds take far less time to make. You can grow a full carat diamond in a lab in under 1 month.

It may only take you a couple of weeks. They’re beautiful and crystal clear, but they’re not worth nearly as much. You can understand why.

How Much Are Raw Diamonds Worth?

There isn’t a one-size-fits-all answer to the question of worth when it comes to valuing raw diamonds. Diamonds vary in color and clarity based on the environment where they formed.

Some diamonds may have few inclusions while others have more that are less discreet. 

All of the factors mentioned above are things that determine the value of a diamond. The one thing you can count on is any genuine raw diamond is worth something. It’s just a question of how much it’s worth. 

Diamonds with few imperfections and less color in them are worth more than those that are tinted yellowish or brownish or that have quite obvious imperfections. 

Diamond FAQs

Can you grow diamonds at home?

You can grow diamonds at home, according to scientists. The idea is to put a tiny piece of a diamond in the microwave along with carbon gas.

You then can use the microwave to create the heat and pressure needed to bond the carbon atoms together and grow a diamond.

The diamond is made from the same atoms and has the same structure as a natural diamond.

Does coal make diamonds?

No, coal does not turn into diamonds. This is a myth. Coal wasn’t even a thing until well after the Earth’s diamonds were created.

Coal comes from plants. Plants were not around when diamonds were forming in the mantle.

How do diamonds get to the surface for mining?

Most diamonds are formed in the mantle. The mantle is far too deep for us to get to for mining purposes.

Diamonds make their way up toward the surface with the help of a volcanic activity. They are transported through the pipes of volcanoes to depths that are easier for us to dig to.

How are raw diamonds mined?

Diamonds are found in the kimberlite pipes of volcanoes. Diamond miners must uncover the pipes by digging through sand and removing the rock.

Then they blast the pit with explosions that break apart the ore.

The ore can be collected once it is broken into manageable pieces. This concept is called open-pit mining.

Can raw diamonds be found anywhere?

Raw diamonds are not found just anywhere. They grow in specific environments where the heat and pressure are just right.

The world’s diamonds come from just seven countries.

Are diamonds used for anything besides jewelry?

Only between 20 and 30% of all natural raw diamonds are used in jewelry pieces. The rest of them are used in various ways across the industry.

One important use of diamonds is for cutting hard materials. They also drill and polish.

Diamonds are also used in the medical field. In particular, they’ve been used in cancer treatments, dental treatments, and vision treatments. 

Other uses include electronics, beauty products, computer hardware, and in smartphones.

How are raw diamonds cut and polished?

The process of cutting and polishing raw diamonds is long. Most diamonds today are cut by a machine. However, they can be cut by hand. There are still a few diamond hand-cutters left around the world. 

For the most part, the diamond you purchase will have been cut by a machine. The process starts with planning, which usually takes place on a computer.

Then, the diamond is sawn into the desired shape. Other stages include the table, the pavilion facets, the crown, and the final bruting. Finally, the whole thing must be polished and finished. 

What can cut a diamond?

Diamond cutting is done with a copper saw. You may be wondering how this is possible when the diamond is harder than copper. The truth is, the copper isn’t what cuts the diamond. Diamond cuts the diamond. 

When the copper saw comes in contact with the diamond, it produces diamond dust. The diamond dust then begins cutting through the diamond. The cutting process usually takes from 4 to 8 hours to complete.

What is a diamond expert called?

A diamantaire is an expert specializing in diamonds. Not all jewelers are diamantaires. These are highly educated, trained, and experienced individuals who are well versed in all things diamond.


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Final Thoughts

A raw diamond won’t always be easy to identify. To the naked eye, it might look just like a stone or a piece of glass.

But there are some tests you can try to see if you’ve found a genuine raw diamond. You can use water, heat, light, your breath, and scratching to see if you might have a true gem. 

Though you can’t find raw diamonds in most parts of the world, if you happen to visit somewhere they come from, be sure you don’t overlook a real raw diamond. You may leave behind a diamond in the rough.



Lindsey graduated with an MBA in 2009. Since then, Lindsey has worked in the retail and consumer service industry as a manager, advisor, and marketer. Lindsey is also the head writer and Co-founder of Lindsey is based in Morgantown, West Virginia.

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