While we recommend isopropyl alcohol for cleaning any nail; maintenance can be managed with dry cotton swabs as well. This is different from the opaque which required iso alcohol maintenance to avoid black carbon spots. The bottom is engraved and that engrave becomes visible through the top of the bucket when the surface is wet. When the floor is dry, the engrave is again hidden by the opacity of refracting light.
Opaque Quartz is used in the scientific glass industry for its superior ability to reduce dissipation of heat compared to clear quartz, which means more efficient vaporization of the concentrate when you dab!