This quickly degrades into another chemical, dimethyl sulphide, which generations of those subjected to unimaginative school lunches will instantly recognise.
This would involve using sulphur or hydrogen sulphide aerosols so that sulphur dioxide would form clouds, which would, in turn, lead to a global dimming.
In 1975 a lorry driver, Thomas Carroll, died after inhaling lethal hydrogen sulphide fumes given off by two toxic loads dumped in Pitsea, which made the press across the UK.
The raw material that is dug out of the ground is bound up in sulphides or oxides, and thus needs refinement (99%-pure copper is barely good enough to be used as electric wire).