is a protected natural area administered by the Bureau of Land Management north of Kremmling, Colorado. Absolutely worth a visit and absolutely NO collecting!
The site is strewn with many dozens of these incredibly preserved specimens.
Typical ammonite mold, approximately 75 cm in diameter. Note the light-colored nacre (mother of pearl) material immediately to the right of my foot.
Detail present on several specimens showing interior chambers and suture pattern. Based on these details, the species has been identified as Placentceras meeki.