Revenu Quebec says 1,920 charges have been laid in all, including 120 against Kitco Metals Inc. and another 120 against company president Bart Kitner. Fines sought from them total more than $454 million.
The agency alleges false statements were submitted in order to illegally obtain tax credits and reimbursements.
Revenu Quebec is also targeting 13 administrators of the jewelry businesses and an accountant.<
Kitco issued a statement on its website to deny the allegations.
The company alleges Revenu Quebec has previously directed a witness to provide false testimony about Kitco in legal proceedings.
''Kitco Metals Inc. has never made false statements in a return nor attempted to obtain a rebate to which it is not entitled,'' the statement said.
The crimes are alleged to have taken place between March 2008 and August 2010.
Revenu Quebec said Monday the alleged fraud centred on the processing of gold.
''This is a major investigation for Revenu Quebec and, without a shadow of a doubt, one of the biggest in our history,'' said agency spokesman Stephane Dion.
Kitco has already filed a $122-million suit against Revenu Quebec in Superior Court and says the damages will increase because of the agency's announcement on Monday.