Gary Green Jasper Identification Guide

What Gary Green Jasper Looks Like

Gary Green jasper — also known as Larsonite — is a famous green scenic/picture jasper that is actually jasperized (silicified) petrified wood from Oregon. It shows soft olive-green to sage and forest-green tones, often with cream, tan, brown, and black dendrites and mottling that create landscape-like "scenes." It is opaque with a waxy to dull luster that polishes to a smooth, glassy finish. Patterns are swirly, mottled, or scenic rather than banded.

Key visual cues

• Muted green base with cream/tan/black scenic mottling
• Opaque, waxy when raw; high glassy polish when finished
• Smooth, even microcrystalline texture (no visible grains)
• Sometimes faint wood-grain or moss-like dendritic markings

Step-by-Step Field ID Checklist

1. Confirm it's jasper (chalcedony/quartz). Waxy luster, conchoidal fracture, no cleavage.
2. Test hardness. It scratches glass and steel (Mohs ~6.5–7).
3. Look at the pattern. Green scenic mottling with earthy accents typifies Gary Green.
4. Check opacity. Jasper is opaque even on thin edges.
5. Streak it. White streak (despite green color).
6. Note origin clues. Material is sourced from a specific Oregon deposit; wood-grain hints point to its petrified-wood origin.

Diagnostic Tests

• Mohs hardness: ~6.5–7 — scratches glass; a knife will not scratch it.
• Streak: white.
• Cleavage/fracture: no cleavage; conchoidal fracture with sharp edges, typical of cryptocrystalline quartz.
• Density: ~2.6 g/cm3 (quartz-like).
• Acid: no reaction (distinguishes it from green carbonate rocks).
• Non-magnetic.

Common Look-Alikes and How to Tell Them Apart

• Other green jaspers (e.g., African green, rainforest jasper): all are hard chalcedony; distinguish Gary Green by its specific muted sage-green scenic look and Larsonite/petrified-wood origin. True ID often relies on the source.
• Green opal/common opal: opal is softer (5.5–6.5) and often more translucent; it may fluoresce and lacks jasper's crisp conchoidal edges.
• Serpentine/nephrite (green): softer and may feel greasy (serpentine) or tougher and fibrous (nephrite); both differ in luster from jasper's waxy finish.
• Dyed green chalcedony: dye concentrates in cracks and looks uniform; natural Gary Green has organic, varied scenery.
• Moss agate: translucent chalcedony with discrete dendrites in a clear-ish body, unlike opaque mottled Gary Green.

Where Gary Green Jasper Is Found

Gary Green jasper / Larsonite comes from a classic deposit in Oregon, USA (Owyhee/eastern Oregon region), where ancient wood was replaced by silica and tinted green. It is a collector and lapidary favorite cut into cabochons and slabs. Because the look is tied to a single locality, provenance is part of the identification.