Don't try mixing the White with the colours. It has Titanium Dioxide and you'll get settlign with the colours, not to mention throwing off the colour palettes big time.
My suggestions (and only if you want to take the risk with the old white ink)? Take on a big job that requires a white underbase design, but does actually have any white showing. In other words, a design that has white underbase and a dark colour layer completing covering that white underbase. You should be able to use up your white that way. That's what I did once when I had minor white ink/colour contamination.
My suggestions (and only if you want to take the risk with the old white ink)? Take on a big job that requires a white underbase design, but does actually have any white showing. In other words, a design that has white underbase and a dark colour layer completing covering that white underbase. You should be able to use up your white that way. That's what I did once when I had minor white ink/colour contamination.