How a substance looks does not mean it's shitty/good. I've gotten brownish mdma that was meh and not very strong. But I got a white powder mdma that is really good. I've had white/brown/tan and they've all been ht or miss. So saying that because it's powder it's shitty means nothing. I was able to find some mda here and its a very very brown color but it was very strong.
I usually taste it but that means nothing. The stuff I have right now has like a icing sugar feel when you put it on your tongue, feels cold and refreshing and also a very bitter taste. Looks very shiny and you see the small crystals.
But unless you have a test kit or can send it away for testing you'll never know.