VS #1 - Monumental Fossil Palm Frond, 9’ x 4.5’

This monumental fossilized palm frond, preserved in the lithographic limestone of Wyoming’s famed Green River Formation, is an extraordinary specimen of natural history. Measuring an impressive 108 x 54 inches (274 x 137 cm), it captures not only the delicate structure of a once-living plant but also a rare moment in paleoecological time. The frond is complete, including the petiole (stem), which displays several pre-fossilization breaks—likely inflicted by ancient windstorms before it was gently laid to rest on the lakebed over 50 million years ago.

Adding to its scientific and visual interest are two exquisitely preserved Knightia eocaena, small schooling fish endemic to this lacustrine ecosystem. Their presence on the same slab creates a compelling paleoenvironmental tableau—plant and vertebrate, flora and fauna, captured together in a single depositional event.

Particularly notable is the intricate pattern of pale stippling across the frond’s leaflets. These are not mineral intrusions or preservation artifacts, but the subtle traces of ancient herbivory: as the frond grew, it was initially folded, allowing insects to bite through overlapping layers. Upon unfolding, these feeding sites emerged as a delicate, organic pattern—one shaped not just by geologic forces, but by life itself.

This is a fully natural specimen, with no insetting or artificial assembly. The palm, fish, and matrix are preserved in their original association within a single stone plate. The slab was quarried from the Lower Sandwich Bed, a stratigraphic layer lying just beneath the classic “18-inch layer,” and long prized by paleontologists for its fine-grained preservation of Eocene life.

It is quite simply a world-class piece—remarkable in scale, scientific detail, and aesthetic presence. Suitable for natural history museums, botanical research collections, or discerning private collectors with a focus on Earth’s deep-time record.

Geological Context

Formation: Green River Formation

Layer: Lower Sandwich Bed (below the 18” Layer)

Location: Lincoln County, Wyoming, USA

Age: Eocene Epoch (~52 million years ago)

Physical Characteristics

Dimensions: 108 x 54 in (274.3 x 137.2 cm)

Weight: 400 lbs (180 kg)