Okabe T, Mitchell R J, Fairhurst C W
J Dent Res. 1979 Mar;58(3):1087-92. doi: 10.1177/00220345790580031001.
In an HCD amalgam, eta Cu-Sn crystals were found dispersed within gamma1 matrix areas. Previously, eta Cu-Sn phase was thought to form only as part of a reaction zone surrounding Ag-Cu dispersant particles. The eta Cu-Sn crystals found in matrix areas of this HCD amalgam are smaller and more widely scattered than eta Cu-Sn crystals dispersed in the gamma1 matrix of HCSC amalgams.