True pashmina carries a Geographical Indication seal (GI No. 46) — a small, sovereign promise that the fibre was gathered in Ladakh and woven in Kashmir, by hand, on a wooden loom.
But the surest test lives in the hand. Real pashmina is warm before you ask it to be, and a full shawl will pass, whispering, through a wedding ring.
Beware the word blend. A little silk is honest; a little acrylic is not. Ask for the seal, then trust your fingers.