According to the O/U and cRc, composite stone (quartz, granite, marble etc.) counter tops, which is made mostly of stone, but is held together with resin, can be Kashered. As a rule, materials such as metal, wood, stone, natural rubber, plastic (if needed), and fabric can be Kashered.
From The Star-K: Oasis Mediterranean Cuisine Bulgar Wheat
Oasis Mediterranean Cuisine Bulgar Wheat is no longer Star-K certified and no longer bears the Star-K symbol. Some packages were mistakenly sold recently at the