What Are THC Crystals (THCA Crystalline)?

Sophia Delphi May 13, 2022 - 7 min read
Fact Checked
THC crystal on a purple surface

There’s always a “holy grail” of weed products. (And no, we’re not talking about the Holy Grail Kush indica strain that won a Cannabis Cup with a perfect score more than ten years ago.)

Here’s what we mean: no matter how dank your bud may be, there are always experts who say, “yeah, but you’ve got to try this!” At one point, the “this” they referred to may have been kief, hash, or shatter.

These days, “this” means THC crystals, also known as THC diamonds and properly referred to as crystalline.

Crystalline is more than 99% pure, and it’s intensely potent, but there are two common misconceptions about it.

First, crystal may not really be as potent as other weed concentrates.

Second, THC crystals don’t contain any THC.

Let’s unpack all of the surprising details.

What is THCA Crystalline?

Essentially, crystal is a cannabis concentrate that’s been processed so that the only compound it contains is a single cannabinoid like THC or CBD. It’s often called an “isolate,” particularly when the CBD in cannabis is the cannabinoid that’s left. When the process is complete, crystal looks like, well, small crystals.

But we have to immediately deal with one of the misconceptions about THC crystal: there’s no THC in it.

The crystalline substance actually contains a cannabinoid acid called THCA, which is the “precursor” to THC. That means THCA can be turned into THC under the right conditions — and those conditions usually involve heat.

A cannabis product that contains THCA instead of THC isn’t unusual; the flower you buy from a dealer or at a dispensary contains THCA, too. The reason you get wasted when smoking is that the heat that produces smoke also converts THCA into psychoactive THC. The same thing happens when you dab or vape weed products or when you decarb your buds to make edibles.

So it’s not a big deal that properly-processed “THC crystal” is said to be 99.96% pure THCA. (At least, that’s what the scientists behind the process claim.) When it’s time to consume it, it will turn into almost pure THC.

What about the other misconception, the one involving potency? How could anything be more potent than 99%+ THC?

It’s simple.

We mentioned that crystalline only contains one substance, THCA, which means that everything else has been eliminated. In other words, the production process eliminates the naturally-occurring terpenes and flavonoids in cannabis, which work together in the “entourage effect” to boost the effectiveness of THC. Without them, THC crystal may be less potent than some of the other concentrates that can blow you away when you dab them.

What Does THC Crystal Taste and Smell Like?

Ah, you’ve drawn the obvious and correct conclusion.

Terpenes are also responsible for most of weed’s flavor and aroma — so when they’re removed to make crystal, the taste and smell you’d expect from any type of marijuana are also removed.

That means crystal is odorless and flavorless. And even if your primary goal is to get high, “odorless and flavorless” quite possibly isn’t what you expect or desire.

So some producers take one more step before selling diamonds; they add some terpenes back into the mix by putting the crystal into terpene-loaded “sauce,” commonly called diamond sauce. That makes it taste and smell like bud and restores some of the entourage effect for increased potency.

Users who buy pure THC crystal will often use it together with flower or another concentrate to combine the potency of the diamonds with the flavor, aroma, and terps of the concentrate.

One final but important note: you won’t find THC crystal sold by strain. Since the terpenes and flavonoids that distinguish one strain from the next are removed, all that’s left is the same THC that’s found in every strain. Crystal made from Durban Poison will be exactly the same product as crystal made from Gorilla Glue.

How Do You Use THC Crystal?

You have a lot of choices.

The crystals can be dabbed or vaped, and those are the most popular ways to enjoy diamonds. Many people “cap” shatter or wax by sprinkling crystal on top of those concentrates before they dab; that can be smart because of the high THC content in pure crystalline. If you’re vaping, make sure your machine can handle concentrates.

You can also smoke crystal in a pipe or joint. The best way to do that is to crush it and add it to your flower, just like you would do with kief.

Other uses for crystal include decarbing it and using it to make cannabutter or canna-oil for edibles and dissolving it in oil to make potent tincture.

Finally, medical patients may simply consume it without decarbing it. Many studies show that THCA may provide the same or even greater health benefits than THC or CBD.

How Is THC Crystal Made?

A warning before we go further: this is not a process you can do on your own. It’s illegal in many states and dangerous in all of them, and it requires specialized knowledge and equipment to approach the type of potency that high-quality THC crystal provides.

  • First, weed is converted into an extract.
  • Next, the extract is mixed with chemicals that dissolve all of the plant material without disturbing the THC.
  • The product is filtered and goes into something called a rotary evaporator, which uses heat, pressure, and motion to separate all of the components, allowing producers to obtain pure THCA.
  • More chemicals are used to remove impurities.
  • The substance is now in crystal form, but the crystals are dissolved in methanol and filtered to remove leftover chemicals and then put back into the rotary evaporator.
  • Finally, the reconstituted crystals are dissolved in another solvent and filtered to remove more impurities and put into the evaporator one more time.
  • What’s left is 99.6% pure THCA isolate, known as THC crystal.

Again, this was just an informational description of the process used to make THC crystal.

If you want to try it, look for it at a dispensary — or settle for distillate or concentrates like shatter, which is almost as potent as crystal and still contains the other weed components that can boost THC’s potency.

THC Crystals: FAQ

Q: Why can’t they just make THC crystals instead of THCA ones?
A: That’s a good question that deserves a good answer. THC’s chemical makeup doesn’t allow it to take the form of crystals; the only way around that problem is to produce THCA crystals that will be converted to THC when they’re burned, dabbed, vaped, or decarbed. You can buy CBD isolate just about anywhere because CBD is able to take a crystalline form.

Q: Since THC crystal doesn’t contain other cannabinoids, terpenes, or flavonoids, does that mean it’s not as strong as concentrate?
A: It’s a tricky distinction. You could say that it’s “stronger” than any other form of cannabis because of its nearly 100% THC content. You could say that it’s “not as strong” as high-quality distillate because there’s no entourage effect to boost the THC’s effectiveness. Either way, it will still blow your socks off, and you can always add terpenes by the methods we’ve mentioned to amplify its final effect even more.


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