Mined from: Dendrite Butte, Paulina, Oregon, USA 

Era: Miocene epoch
Geological Age: Approximately 5 and 23 mya

Description: Check out our Youtube video on this fossil for more information from our owner: https://www.youtube.com/watch?v=9Z2dFojS-_M

These Agatized Tree Limb Casts hail from the ancient volcanic flows of Dendrite Butte near Paulina, Oregon—fossilized remnants of Miocene-era forests, estimated to date between approximately 5 and 23 million years ago. During this period, volcanic ash and silica-rich groundwater slowly replaced the organic material of fallen trees, preserving their shape in intricate, stone-like detail. What remains are lifelike casts in chalcedony-rich agate, often complete with bark textures, knot structures, and branching features.

Unlike petrified wood, which replaces the original tissue cell by cell, these limb casts are external molds—silica formed around the rotting wood, capturing its outer form before the organic material decayed. That makes these specimens scientifically fascinating: they are not wood, but a geological echo of wood, hardened into beautifully patterned agate over millions of years. The pieces from Dendrite Butte are especially prized for their earthy tones, scenic dendritic inclusions, and their rarity, as the collecting site is no longer publicly accessible.

Mini
Approximate Size of 1 piece: 1.2cm x 1cm x 1cm
Approximate Weight of 1 piece: 1.5g

Small
Approximate Size of 1 piece: 1.8cm x 1.8cm x 1cm
Approximate Weight of 1 piece: 4g

Medium
Approximate Size of 1 piece: 2.8cm x 2.4cm x 1.5mm
Approximate Weight of 1 piece: 10g

Large
Approximate Size of 1 piece: 5cm x 2.5m x 1cm
Approximate Weight of 1 piece: 22g

X-Large
Approximate Size of 1 piece: 5.5m x 4cm x 1.8cm
Approximate Weight of 1 piece: 56g

Quantity: 1pc

We do our best to buy quality products- although not every rock is the same. If you choose to purchase the "staff pick option", we will select the best of the batch for you. Otherwise, it will be at random from the larger batch we have in stock.