<prompt> Which of the following investment material can be heated up to 1200 degrees centigrade?Gypsum bondedPhosphate bondedSilica bondedAll of the above  <response>: When the ethyl silicatebonded investment is heated to a sufficiently high temperature, some silica converts to quartz and provides added expansion. This type of investment can be heated to between 1090 C and 1180 C and is compatible with the higher-fusing alloys. Note- Phosphate bonded investment is heated upto 1050 C.Closest answer is silica bonded investment materials.Phillips Dental Materials ed 12 pg 226 