Bertoia, Harry. UNTITLED MONOTYPE (American, 1915-1978). Ink on rice paper, circa 1970. Unique. Unsigned, Inscribed 453 in ink, lower right. 25 x 12 inches, framed to 30 x 16 inches. In excellent condition.
The 
following is from the section on Monotypes on the website of the Bertoia
 Foundation:
"Bertoia developed his own style of creating monographics 
at Cranbrook Academy of Art in Bloomfield Hills, and never worked with, 
or even met, other printmakers.He would ink up a glass surface, place 
rice paper on the glass, and then create designs with fingers or hand 
tools from the backside of the paper. Each “print” is unique – never 
reproductions of another – and there are thousands of them. When 
Bertoia, looking for critique and direction, sent about 100 monotypes to
 Hilla Rebay at the Guggenheim Museum of Non-Objective Art in 1943, he 
was quite shocked when she asked to purchase the entire stock. He was up
 half the night determining a fee, and finally set $1000 as his 
compensation. When the subsequent Guggenheim show included many of his 
prints, Bertoia’s name gained recognition.Bertoia loved the quickness 
and spontaneity of the medium of his graphics. While sculptures took 
weeks or months to produce, monotypes came to life in mere minutes. The 
series of 50 monotypes reproduced in the Harry Bertoia Fifty Drawings 
book “came into being in about twenty-four hours of uninterrupted work.”
  Most, if not all, of Bertoia’s designs, whether they are chairs or 
sculptures or tonals, were born on paper first. He started the monotypes
 in 1939 and continued throughout his life."