Hi Ian,

Thank you for contacting Mearto with your appraisal inquiry.
Nieto's works have been bringing fairly good prices recently; if you were interested in selling this at auction, I would strongly suggest selling it with an auction house that has a history of selling Western American art.
Based on the photos and information provided, and subject to examination, this is:

John W. Nieto (American, 1936 - 2018)
"Delaware Chief" (undated)
acrylic on canvas, framed
46 by 42 inches
PROVENANCE: acquired at auction
$12,000-18,000*
*represents a fair-market value for auction purposes; retail or asking price may vary.

Please let us know if you have additional items to appraise, and thank you again for using Mearto.