Definify.com
Webster 1913 Edition
Sandiver
San′di-ver
,Noun.
 [Perh. fr. OF. 
saïn 
grease, fat + de 
of + verre 
glass (cf. Saim
), or fr. F. sel de verre 
sandiver.] A whitish substance which is cast up, as a scum, from the materials of glass in fusion, and, floating on the top, is skimmed off; – called also 
glass gall
. [Formerly written also 
sandever
.] Webster 1828 Edition
Sandiver
SAN'DIVER
, n.Glass-gall; a whitish salt which is cast up from the materials of glass in fusion, and floating on the top, is skimmed off.  A similar substance is thrown out in eruptions of volcanoes.  It is used by gilders of iron, and in the fusion of certain ores.  It is said to be good for cleansing the skin, and taken internally, is detergent.