section_path: Types/Silicate glasses/Borosilicate glass
section_name: Borosilicate glass
paragraph_text: Borosilicate glass
  
  Borosilicate glasses (e.g. Pyrex, Duran) typically contain 5–13% boron trioxide (B O). Borosilicate glasses have fairly low coefficients of thermal expansion (7740 Pyrex CTE is 3.25 × 10 /°C as compared to about 9 × 10 /°C for a typical soda–lime glass). They are, therefore, less subject to stress caused by thermal expansion and thus less vulnerable to cracking from thermal shock. They are commonly used for e.g. labware, household cookware, and sealed beam car head lamps.