a video going into details on what the differences are between dye and pigment stains. It also tells you how both react to different kinds of wood (e.g., maple vs. oak). If you buy a can of stain off the shelf, try to stir it with a paint stick. If there's sludge on the bottom and little color on the top, it's pigment only. If there's no sludge, it's dye only. And if there's both sludge and strong color on the upper part of the stick, it's a bit of both. The can won't tell you (and the customer service is unlikely to know, as I found out).