Most velvet sold today is polyester. It is cheap to make, it keeps its shape, and from across a room it can pass. Up close, and once it moves, it can’t.
Velvet is a woven cloth with a pile: thousands of short fibres standing up from a base fabric, cut so their ends face outwards. Where the pile points straight at you, light falls between the fibres and stays there, so the colour looks deep, almost black. Where the cloth bends over a shoulder, you see the sides of the fibres instead, and they send the light back. That is why a velvet poncho is never one colour. In these photographs the Bronze is nearly black in the folds and copper where it turns towards the lamp.
What the fibres are made of decides how far that goes. Polyester is a plastic. Its filaments are round and identical, so the shine is even and a little glassy, and the cloth is stiff enough to stand away from the body. It does not absorb moisture, so it turns warm and clammy over a long evening, and it clings with static.
Silk velvet behaves differently. Its fibres are natural, much finer and smoother, so the cloth is light and falls close to the body instead of standing out. The light moves across it as a soft shimmer rather than a hard shine. It breathes, so it is as comfortable at the end of dinner as at the start.
Silk velvet also takes colour deeply, which is why our ponchos look the way they do: the lemon and pink of the Limoncello, the midnight blue of the Glory of the Snow, the magenta and emerald of the Dahlia Sparkle, the pale blue of the Summer Cloud.
Each poncho is finished by hand, and the difference is easiest to see in person, when it moves. See the ponchos