Diamond surfaces are etched ( 1)by dippiDg into fused potassium nitrate ( 475 -525℃ ) and 〔 2) by heating in a rbon arc to a high temperature ( 酎 800 °C ) and then pouring a drop of saturated aqueous Eolution 【 )f potassium nitrate on it , and the structure of etched sur 魚 ces and 血 e corresponding light figUres are Qbserved . The ( 111 ) sur 工 ace etched by both lnethDds is covered with etch pits of triangular pyramidal shape , some of them pDinted and others truncated , sutrounded by side

more »

... s which lncline at an angle of 11 . 5 °against the ( 111 ) plane and correspond to the { 885 } Planes . On the ( 100 ) surface et (血ed by 血 e latter method , etch pits of tetragonal pyramiCl of which side faces incline at an angle