It's a presence of pads, which seems to lend their characteristics to the crystal. Here is the christal. It looks more or less colorless. And now suppose i bring a pink piece of paper behind it. But while it looks pink, it's not pink, actually, not at all. Nothing has become pink about it. Even when it looks yellow, it nothing about it is actually yellow. So this thing is the pad. Now what is a pad? Body is a lupa for consciousness. Mind is an pad. The world is an paddy. The universe is a pad.