Test items   specifications   test results
Appearance   red powder   similar
Content of fe2o3   96.0% min   96.2%
Volatile at 105 deg. 1.0% max   0.59%
Soluble in water   0.3% max   0.15%
Residue (320 mesh) % 0.3% max   0.10%
Oil absorption   15-25 %   19.2
pH of water extract 3-7   3.6
Shade   close to standard close
Tinting strength   98-102 %   100.1%