长轴面 meaning in Chinese

macropinacoid

With light stones , on the other hand , the table surface should be perpendicular to the longitudinal axis , in order to receive more depth of colour
浅色碧玺时，其桌面必须和长轴面成直角，才可将其颜色完全充分显现出来。
In the raw crystal , he has to orientate the table surface in such a way as to achieve the best possible colour and the best possible weight , while attempting as far as possible to keep out the less beautiful , darker colour
切割深色碧玺时，碧玺的桌面必须平行于晶体的主轴面，反之，切割浅色碧玺时，其桌面必须和长轴面成直角，才可将其颜色完全充分显现出来。