Green Onyx Egg — Banded Green Chalcedony, Polished, 314g — Field Find

THE FIND
A polished green onyx egg, 314g — soft layers of banded green tones with a smooth, dense finish. The banding shifts as the egg turns, each layer a slightly different shade. A grounding, composed piece that suits a collection or a desk without demanding attention.

WHAT WE KNOW
Green onyx is a trade name for green banded chalcedony — microcrystalline quartz — where the banding runs in parallel layers. The green color can be natural (from trace chromium, iron, or other impurities) or the result of dyeing, which is common in commercial green onyx on the market. It is worth noting that much material sold as “green onyx” is either dyed chalcedony/agate or banded calcite/aragonite (which is softer at Mohs 3–4 vs. quartz at Mohs 7). The material identification of this specimen has not been independently laboratory verified and is presented based on catalog identification. At 314g this is a substantial egg with real display presence. Locality not independently verified.

THE STORY
The banding in onyx-family chalcedony is a depositional record — each layer represents a period of silica-rich fluid moving through a rock cavity and depositing material on the cavity wall. The color variation between bands reflects differences in mineral impurities in the fluid at each depositional event. In a polished egg, those layers become a cross-section through that history — a record, compressed into a form you can hold.

WHY WE CHOSE IT
The banded green tone is consistent and the polish is clean. At 314g it has significant weight and shelf presence — one of the heavier eggs in the collection. A composed, grounding piece for a mineral or lapidary collection that doesn’t need to announce itself.

ABOUT THIS PIECE
Type: Green onyx egg (banded chalcedony, polished carving — catalog identification; natural color vs. dyed not confirmed; not independently verified)
Weight: 314g
Locality: Not independently verified
Condition: Polished carving — please review photographs for banding, color, and natural variation.
Quantity: 1 — one of a kind.