CRC stands for "Color Remediation Column" and is a process used in the cannabis industry to remove impurities from extracts and enhance visual aesthetics. It is a type of cannabis extract that is made using a process called "column chromatography". CRC has evolved and is now used to remove pesticides, unpleasant flavors, and other unwanted byproducts. It is most commonly used with butane hash oil. The color of low-grade hash oil changes from nearly black or dark brown to light gold or even white when it undergoes CRC. One of the downsides of CRC is that it will also strip a concentrate of its terpene content. The safety of CRC hash is up for debate, and the research and safety data on CRC tech products remain thin. Some people say that CRC wax is bad for you, while others argue that it is safe. The debate is rooted in the fact that CRC removes terpenes, which are essential oils that give cannabis its flavor and aroma.