ArtValue.ca has 13 auction art sale records for their charcoal drawing results, with prices in the range of C$100 to C$250.
charcoal on paper
Lot for sale by Waddington's Auction House, Toronto
Thu, Oct 5, 2017
Estimate $600 - $800
Sold for CAD $240
mixed media on paper
Dimensions - 55.88 cms x 76.2 cms (22 ins x 30 ins)
Lot for sale by Saskatchewan NAC Auction House, Regina
Sat, Apr 9, 2016
Estimate $500 - $1,000
Sold for CAD $220
Saskatchewan NAC Auction House Biography and Notes
Alan Sonfist was born in New York City in 1946. He is most associated with the Earth Art Movement. He has said "My art presents nature. I isolate certain aspects of nature to gain emphasis, to make clear its power to affect us...". His first solo exhibit was in 1970 and he has since exhibited extensively in the U. S. and abroad. His work is similarly found in collections around the world including the Metropolitan Museum of Art, the Guggenheim and Centre Georges Pompidou in Paris.