Concentrates, in case you haven’t heard, are all the rage these days. Smoking them is less harmful than burning herbs, and they’re increasingly being used as a consumption method of choice.

But how are they made? Well, the whole thing is more simple than it may seem. First you soak plant matter in a solvent, a process that extracts a thick, concentrated oil. Then you remove the solvent from the oil by evaporating it off.

You can make concentrates using numerous different solvents, but the most commonly used is butane. Butane is more dangerous, but it’s also more popular. CO² is another increasingly popular solvent that produces cleaner oil. Here is a brief explanation of how to make concentrates.

Gather supplies

First, get yourself a few supplies. These include an “extractor,” one or two canisters of liquid butane, some ground herbs, a double boiler, an electric hot plate, a Pyrex glass container, a few single-edged razor blades, and some parchment paper.

Precautions to take

But a serious word of caution: Butane is extremely flammable. That’s why it’s used in cigarette lighters. Do not spray it indoors, close to buildings, or near vehicles, as any spark is liable to cause an explosion that could level your house and burn you alive. No kidding.

The extractor is a tube made of plastic or glass. You can use a length of PVC piping, but be aware that toxic chemicals could leach into your product. The extractor should have a single small hole at one end and a removable cap at the other. There should be several small holes in the cap, with a filter on the inside of it; a coffee filter cut to size should do fine.

1. Place ground herbs inside extractor tube

Start by placing ground, dry herbs inside the extractor.  Ideally, you should fill the tube, but make sure it isn’t packed too tight. You want enough space for the butane to evenly saturate all the herbs.

2. Soak herbs with butane

Take a canister of butane, insert the nozzle into the hole at the top of the extractor, and spray away. Use up the entire canister; you may need a second depending on the amount of plant matter being used. The idea is to soak the herbs until a greenish-brown oil starts seeps through the filter and out the holes at the bottom off the extractor. This is your herbal extract. Let it drip into your Pyrex container.

3. Evaporate off the solvent

The next step involves separating the solvent (butane, in this case) from the herbal extract, an evaporation process which takes place over time, and can be sped up with the application of heat. By simply exposing the solution to air, the butane will gradually evaporate over time, which will be apparent by the “bubbling” that occurs on the surface of mixture.

To increase the rate at which the butane evaporates from the solution, leaving just plant extract, you can apply heat to the Pyrex dish. Given the highly flammable nature of butane, it is highly recommended that you perform this stage outdoors, clear of any buildings and vehicles, with plenty of ventilation.  Using an extension code, set up an electric hot plate on a flat surface outdoors. Place your Pyrex container on top of it and set the hot plate to a low heat. The process should not be rushed, so do not heat the plate too high in an attempt to speed up the process. You will begin to see bubbles forming on the surface of the solution, and this will continue as all of the butane evaporates away from the herbal extract. Once all butane has been removed from the solution, no more bubbles will form, and all you will be left with is potent herbal extract. It’s important to ensure every last bit of the solvent is evaporated to minimize the chance of leaving any residual butane in your extract.

4. Store it for later

At this point you’ll have a thick, near-solid oil at the bottom of the container. This is your finished product. Scrape it up with the razor blades while still warm, and then place it on parchment paper. Let it cool and fold up the paper to store your concentrate, or, if you like, transfer it all to non-stick container.

And that is how to make concentrates. Always keep in mind how dangerous this process can be, always work outside, and don’t even think about lighting a cigarette anywhere near your work space. Most important, though, enjoy your concentrates!