Orange-red birefringence of gold particles in paraffin wax embedded sections: an aid to the diagnosis of chrysiasis.

Chrysiasis, the systemic deposition of gold pigment in patients on long term chrysotherapy, is identified histologically as small black granules within macrophages. Histological sections from 12 confirmed cases of chrysiasis were examined under crossed polarized light. This revealed a striking orange-red birefringence of the pigment not detected in other histologically similar deposits. This technique provides a valuable adjunct to the histological identification of gold without the need to resort to ultrastructural and analytical procedures.