Cyanidation processes for the extraction of gold or silver frequently invol
ve the processing of sulfur-containing solids that react with cyanide to fo
rm thiocyanate. The formation of thiocyanate is an undesired side reaction,
and in many cases thiocyanate formation results in a prohibitively high cy
anide consumption. With the increasing number of gold and silver mining pro
jects that involve the processing of sulfide ores or concentrates or that u
tilize a biological sulfur oxidation process, more attention is being focus
ed on minimizing thiocyanate formation and in treating solutions to elimina
te toxicity associated with thiocyanate. Though not yet commercially applie
d, there are several processes available to recover cyanide from thiocyanat
e to reduce tailings toxicity and to allow the reuse of cyanide otherwise l
ost to thiocyanate formation. This paper presents an overview of processes
available for recovering cyanide from thiocyanate along with estimated oper
ating costs for the processes. Pilot testing data suggests that in some cas
es cyanide can be recovered from thiocyanate for approximately the same cos
t as newly purchased cyanide.