Quartz after American Elm (Petrified Wood)

specimen number:
2292110

location:
Vantage, Washington, USA

description:
A beautiful cut and polished slab of petrified wood. This is said to have been in the American elm tree.

The petrified wood specimens found near Vantage, Washington, represent a remarkable example of structural preservation where original organic wood cells of American elm (Ulmus americana) have been entirely replaced by microcrystalline silica, primarily in the form of chalcedony and quartz. Geologically, these specimens originate from the Miocene-aged Vantage Sandstone Member, which is sandwiched between massive basaltic lava flows of the Columbia River Basalt Group. Around fifteen million years ago, extensive volcanic eruptions triggered massive mudflows and ash deposits that rapidly buried localized hardwood forests, creating an anoxic environment that prevented decay. Over thousands of years, silica-rich groundwater percolating through the porous volcanic sediments slowly dissolved the organic cell walls, simultaneously precipitating microscopic quartz crystals within the cellular voids. This slow, atom-by-atom silicification perfectly mirrored the intricate structural anatomy of the elm, leaving behind highly durable, colorful stone logs that still clearly display growth rings, bark textures, and microscopic vascular pathways.

Questions about this specimen?
Send an email or call us: 314-341-1811.