Supply and demand. As the number of units remaining
drops, the price goes
up. This, for example, is clearly his last piece of "blanc" paper:
https://www.ebay.co.uk/itm/Blanc-sheet-of-paper-04/254895244594 (or maybe
it's French paper ...) :-)
The ordinary paper that consumers use throughout their everyday life such
as newspapers, books, cereal boxes, etc., is primarily made of wood pulp;
however, the paper should be composed of 75 percent cotton and 25 percent
linen. This is what gives it its distinct look and feel. The security
thread, and portrait or numberal watermarks should be already built into
the paper when it is received. A 6mm wide 3-D security ribbon should be
woven into the paper. Tilt the note back and forth while focusing on the
blue ribbon. You will see the bells change to 100s as they move. When
you tilt the note back and forth, the bells and 100s move side to side.
When you tilt it side to side, they move up and down.
The sheet of paper should be large enough for multiple images, which can
be cut apart later.