C\u00e1t th\u1ea1ch anh l\u00e0 m\u1ed9t lo\u1ea1i kho\u00e1ng v\u1eadt c\u00f3 ph\u1ed5 bi\u1ebfn trong l\u1edbp v\u1ecf Tr\u00e1i \u0110\u1ea5t. \u0110\u00e2y l\u00e0 lo\u1ea1i c\u00e1t c\u00f3 th\u00e0nh ph\u1ea7n ch\u00ednh l\u00e0 th\u1ea1ch anh, l\u00e0 v\u1eadt li\u1ec7u l\u1ecdc n\u01b0\u1edbc c\u00f3 k\u00edch th\u01b0\u1edbc nh\u1ecf, d\u1ea1ng h\u1ea1t, nhi\u1ec1u g\u00f3c c\u1ea1nh, c\u00f3 m\u00e0u tr\u1eafng \u0111\u1ee5c ho\u1eb7c v\u00e0ng n\u00e2u. C\u00e1t th\u1ea1ch anh c\u00f3 h\u00e0m l\u01b0\u1ee3ng SiO2 r\u1ea5t cao, tr\u00ean 95%. Lo\u1ea1i c\u00e1t n\u00e0y \u0111\u00e3 \u0111\u01b0\u1ee3c \u1ee9ng d\u1ee5ng \u0111\u1ec3 lo\u1ea1i b\u1ecf ch\u1ea5t b\u1ea9n trong n\u01b0\u1edbc khi\u1ebfn n\u01b0\u1edbc trong s\u1ea1ch h\u01a1n.<\/p>\n
C\u00e1t th\u1ea1ch anh\u00a0<\/a>c\u00f3 th\u00e0nh ph\u1ea7n h\u00f3a h\u1ecdc l\u00e0 Si (Silic), ngo\u00e0i ra n\u00f3 c\u00f2n ch\u1ee9a m\u1ed9t s\u1ed1 nguy\u00ean t\u1ed1 h\u00f3a h\u1ecdc kh\u00e1c nh\u01b0: CO2, NaCl. H2O, CaCO3,\u2026 v\u00e0 \u0111\u01b0\u1ee3c d\u00f9ng trong qu\u00e1 tr\u00ecnh x\u1eed l\u00fd n\u01b0\u1edbc th\u1ea3i, l\u1ecdc n\u01b0\u1edbc tinh khi\u1ebft, n\u01b0\u1edbc sinh ho\u1ea1t cho h\u1ed9 gia \u0111\u00ecnh,\u2026. Tr\u00ean b\u1ec1 m\u1eb7tc\u00e1t th\u1ea1ch anh<\/a> s\u1ebd xu\u1ea5t hi\u1ec7n l\u1edbp m\u00e0ng b\u1ecdc v\u00e0 ch\u00fang s\u1ebd h\u1ed7 tr\u1ee3 qu\u00e1 tr\u00ecnh l\u1ecdc t\u1ed1i \u01b0u nh\u1ea5t. B\u00ean c\u1ea1nh \u0111\u00f3, h\u1ee3p ch\u1ea5t s\u1eaft 3 oxit Fe(OH)3 s\u1ebd t\u1ea1o ph\u1ea3n \u1ee9ng k\u1ebft t\u1ee7a, khi \u0111\u00f3c\u00e1t th\u1ea1ch anh<\/a> s\u1ebd h\u1ea5p th\u1ee5 Asen.<\/p>\n