Agatized Cycad Wood is a fossilized remain of ancient cycads where organic material has been replaced by microcrystalline silica. Collectors look for well-defined internal structure, such as the characteristic pith, cortex, and vascular bundles visible in polished cross-sections.

Hardness

6.5-7

Mohs

Luster

Waxy

Streak

White

Transparency

Translucent

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Agatized Cycad Wood

Also: Silicified Cycad, Petrified Cycad

Hardness: 6.5-7
Luster: Waxy
Streak: White
Transparency: Translucent

No image

Is this agatized cycad wood?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

1
Test the hardness
Try to scratch agatized cycad wood with a known reference. Agatized Cycad Wood sits at Mohs 6.5-7 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Agatized Cycad Wood leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Agatized Cycad Wood typically shows a waxy luster.
4
Match the color range
Compare against the expected color range: brown, tan, gray, white, black, red.
5
Look at form & habit
Typical habit: massive.

Often confused with

Agatized Cycad Wood vs. its common look-alikes — and how to tell them apart in the field.

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Wood Opal

Mohs 5.5-6.5

How to tell apart: Luster reads waxy on Agatized Cycad Wood and vitreous on Wood Opal.

Often found alongside agatized cycad wood

Minerals reported to co-occur with agatized cycad wood. Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula: SiO₂
Mohs hardness: 6.5-7
Density: 2.6-2.7 g/cm³
Colors: Brown Tan Gray White Black Red
Streak: White
Luster: Waxy
Transparency: Translucent
Crystal habit: Massive
Cleavage: None
Rarity: Uncommon
Uses: Lapidary, Collector, Decorative
Host rock: Sedimentary Strata
Typical price: $10-200 depending on preservation and coloration

Where rockhounds find agatized cycad wood

Classic worldwide localities

Black Hills, South Dakota USA
Utah, USA
Wyoming, USA
Madagascar

Field-hunting tip

Look in sedimentary strata country — that is the host setting where agatized cycad wood typically forms. If you start seeing quartz, chalcedony, jasper in float, you are in the right ground. Field specimens usually show a massive habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify agatized cycad wood?+

Mohs hardness is 6.5-7. It typically shows a waxy luster. The streak is white. Common colors include brown, tan, gray, white.

Where is agatized cycad wood found?+

Notable localities include Black Hills, South Dakota USA; Utah, USA; Wyoming, USA; Madagascar.

How much is agatized cycad wood worth?+

Typical asking prices fall in the range of $10-200 depending on preservation and coloration. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like agatized cycad wood?+

Agatized Cycad Wood is most often confused with Wood Opal, Flint Nodules, Chalcedony. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with agatized cycad wood?+

Agatized Cycad Wood commonly co-occurs with Quartz, Chalcedony, Jasper, Calcite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does agatized cycad wood form in?+

Agatized Cycad Wood typically forms in sedimentary strata. Working float back to the host body is the standard way to chase a fresh occurrence.

What is agatized cycad wood used for?+

Agatized Cycad Wood is used in lapidary, collector, decorative.

Find agatized cycad wood on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.