Question: what is the difference between soft glass and hard glass?
Answer: “Hard-glass” is an acronym for borosilicate glass, like Pyrex or Kimax. “Soft-glass” is an acronym for soda-lime glass, or a higher expansion type glass, (88-92 COE). Lab glass is generally made from “hard-glass”, (borosilicate). Bottles are generally made from “soft-glass,” or soda-lime glass.