Abstract:The geometric constants of a ctystal should be in accord with the cell parameters of thecrystal. In the book “Atlas of Placer Minerals”,however,the drawings of crystal form(100) ofanatase,zircon,thorite,xenotime,vesuvianite, scheelite and wulfenite are identical to those oftheir unit cell(110)due to the old,but wrong crystal orientation.Acorrection for these errors has been made by the author.First,the crystal plane indices andrelevent angles of these minerals are calculated according to both the old and ne...