While referring to a specific grade of hash or rosin, 90μ is more of a slang term. μ referring to microns, which measure the size of the openings of the filter screen, and allow for the separation of trichomes from plant material. Hash is filtered through a series of mesh screens, the 90μ screen comes after a 120μ screen, so the resulting hash would actually be a range from 90-119μ. The 90-119μ range is widely considered the top tier of hash, though products are typically available in a number of different ranges.
🔊 nine·ty my·kron
In the Wild — Example
I only like to smoke 90μ hash rosin.
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