Patent ID: 8420192

Claim:
A silica container comprised of: a substrate having a rotational symmetry, a peripheral part of the substrate comprising a silica and a white opaque layer part that contains gaseous bubbles, an intermediate layer formed on an inner wall of the substrate, the intermediate layer comprising a silica, and an inner layer formed on an inner wall of the intermediate layer, the inner layer comprising a colorless and transparent silica glass not substantially containing gaseous bubbles, wherein: the substrate contains: each of Li, Na, and K, a total concentration of the Li, Na, and K present in the substrate being 300 or less ppm by weight, and an amount of H 2 O molecules released upon heating of the substrate at 1000° C. under vacuum is 3×10 17 or less molecules/cm 3 , the intermediate layer contains: a concentration of OH groups in a range from 10 to 1000 ppm by weight, and at least one compound selected from the group consisting of aluminum and crystal nucleating agents, a total concentration of aluminum and crystal nucleating agents present in the intermediate layer being in a range from 10 to 1000 ppm, and the inner layer contains: a concentration of OH groups in a range from 1 to 200 ppm by weight, each of Li, Na, and K in an element concentration of 60 or less ppb by weight, and each of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, Ta, and W in an element concentration of 30 or less ppb by weight.