Strontium oxalate
From PyroGuide
Formula: SrC2O4.H2O
Description: A fine white, insoluble powder made by precipitation. The water content may be a drawback. It is sometimes used to obtain red colours (even if more expensive than the carbonate) and in some glitter formulas together with gunpowder and Al. Do not use in chlorate mixtures and keep it away from acids.
Hazards: Strontium oxalate is harmful by skin contact, inhalation and ingestion as it is a salt of oxalic (ethanedioic) acid, it can cause renal failure and may even prove to be fatal if ingested.
Hazard Symbols: Xn