Complying with California law
We designed our process both to achieve an extremely high level of purity and also to comply with California law, which prohibits the use of chemical extraction or synthesis for controlled substances. Purification without prohibited chemicals posed a challenge, but we developed other methods over several years to address each undesirable contaminant group. We believe our process is patentable but have not filed a patent disclosure, pending further clarification of the applicable laws.
The legal details: California code section 11379.6(a) prohibits "chemical extraction" of controlled substances but does not define the term "chemicals." However, the Court ruled in The People v. Bergen that resin can be "physically extracted" (e.g. pressure) or by "leaching the resin from the plant material by dissolving it in a nonchemical…extractor, such as butter." The unfortunate lack of legal precision leaves everyone guessing. However, the Court did bless physical methods such as pressure (and by extension other physical methods such as centrifugation) as well as extraction ("leaching") by butter. By extension, this might also include similar non-chemical, food-grade solvents, such as carbon dioxide, vegetable oil, glycerin and orange oil (d-
limonene); however, neither the law or court decision adequately defines this.
Our refining process uses no chemicals (as defined above) whatsoever. Our only consumables are added to formulate PureGold for pharmaceutical uses. Our soft-gels contain gelatin and glycerin in the capsule, and grape seed oil to aid absorption of the cannabinoids. Our sublingual spray contains Everclear (food-grade alcohol), used to enhance the absorption of cannabinoids through the oral mucosa, and a bit of peppermint oil for flavoring. Our PureGold contains 5% food-grade d-
limonene — a terpene that occurs naturally in cannabis.
We add absolutely nothing else in the PureGold process or to any PureGold product.
Making PureGold
Many cannabis dispensaries feature cannabis concentrates alongside their cannabis flower products. Concentrates are commonly known as "hash" or "hash oil." The PureGold process starts with commercial "hash oil," or cannabis resin. We remove solid materials such as mold, insect parts, cellulose, hemicellulose and lignin. We also remove man-made impurities such as pesticides, fungicides and herbicides. And we remove undesirable plant products such as fats, waxes, flavonoids, pectins, chlorophyll and tar. We select certain classes of
terpenes and terpenoids that are known to have therapeutic effects, and reject others that have no therapeutic value. What's left is a highly purified concentrate that consists of 95% cannabinoids in their natural proportions and 5% therapeutic sesquiterpenes.
Even when the refining process has been completed, the result still is not ready to be called PureGold. As a final step, we have each lot rigorously tested by independent laboratories. Only after it has passed our demanding quality control screening can our key ingredient bear the name PureGold. We don't just claim to make pharmaceutical-grade cannabis products.
The following diagram shows an idealized view of common cannabis flower contents along with their relative proportions. The active ingredients — cannabinoids and sesquiterpenes — comprise less than 20% of the total. All the rest is extraneous material.
Cannabis concentrates are made from either flowers or leaves. First, the cannabis is dried and screened. Then the solvent is added, dissolving the resin and leaving a cellulose residue behind. The solvent, now bearing the dissolved resin, may be treated further to remove more undesirable components. Finally, the solvent is removed by some form of evaporation.
Common solvents include butter, vegetable oil, glycerin, alcohol, carbon dioxide, butane and hexane. Along with the desired cannabinoids, every solvent also extracts undesirable constituents, such as tar, chlorophyll,
terpenes, waxes, flavonoids and sugars. That's why "hash oils" smell funny, taste funny and leave a substantial residue after heating. These non-therapeutic impurities also have physiological side-effects, such as "cotton mouth" and a "dopey" feeling of mental confusion.
In other words, some undesirable constituents go into solution in the solvent and are unavoidably carried forth into the essential oil. Hash oils generally contain around 50% cannabinoids along with 50% extraneous compounds. We remove those extraneous compounds.
The following diagram shows the results of this initial extraction step. Notice that most of the extraneous material is no longer present, and that the cannabinoids are now about 50% of the total.
A closer look
We identify undesirable compounds in the provided essential oils and use our proprietary processes to remove them. Our processes address each contaminant group one by one until only the cannabinoids remain. In all, TetraLabs' processes contain about forty steps. Purification takes about three weeks, utilizing advanced equipment and skilled personnel.
Using only heat, pressure, centrifugation and other physical methods, we isolate and remove each of the groups of undesirable compounds shown in the diagram above of essential oils. Only the cannabinoids and trace amounts of sesquiterpenes and pigments remain, as shown in the following diagram.
Achieving purity
After removing all contaminants and revealing the pure cannabinoids, the end product weighs at least 50% less than the essential oils with which we started. In the process, we accumulate collections of tar-like substances, wax and
terpenes.
The final product that emerges from the TetraLabs process is a pale yellow, crystal-clear, viscous oil containing only cannabinoids. Its consistency is somewhat thicker than molasses but thins down to a runny liquid at about 160˚F. When warmed, PureGold has a pleasant, sweet aroma from the sesquiterpenes.
The color and clarity of PureGold attest to its purity. Moreover, when a few drops of PureGold are evaporated on a glass plate or in a new vaporizer, no residue remains. The glass appears completely clean. This test yields substantial charred residue with any other cannabis concentrate.
Regardless of the material given to us, finished batches of PureGold are nearly identical. More specifically, the relative percentages of the various cannabinoids vary insubstantially from batch to batch.