My reagent ninhydrin has gone bad and I don't plan on buying again anytime soon. For my precipitate this can only be mescaline malate OR malic acid. I started with unwashed mescaline hcl. The first precipitate was NOT mescaline but likely calcium malate. The easiest way to test is getting a portion and adding hcl to see salt formation.can you not run a quick tlc plate to confirm what is precipitating