W035 / Oregon, Nevada

McDermitt regional lapidary materials

Regional umbrella; not a single material

McDermitt is a place-name shared by different lapidary materials. Start by identifying what the piece is before narrowing where it came from.

← Western Lapidary Materials
Reference photograph pending

What it is

Regional umbrella; not a single material

What to look for

Regional material can include very different patterns and structures. This umbrella intentionally has no diagnostic color tags.

At the cutting bench

Determine whether the piece is opal, silicified wood, chalcedony or another material before choosing storage and cutting methods.

Under the loupe

Do not merge Purple Cow, Gary Green, thunderegg beds and unspecified McDermitt material into one identity. Bed-specific source evidence is needed.

Source & collecting access

Individual claims, tribal/private land, closures and mine workings require separate permission checks. No current collecting access is asserted.

Status checked 2026-10-03

The market notebook

No verified realized-price range was established for this entry. Asking prices and sold labels are not interchangeable.

Market researched 2026-10-03

Open the field notes

Formation & evidence

USGS documents a caldera, volcanic rocks, lake sediments and hydrothermal mineralization. This regional framework does not establish the formation history of every traded jasper, opal or wood specimen.

Collecting & trade context

Old labels may use McDermitt loosely. Keep the original wording and associated pieces; Oregon versus Nevada needs documentary evidence.

Reading an old label

Preserve the exact name, dates, wrapping and associated pieces. Old-stock age alone does not authenticate a locality or imply exceptional value.

Color comparison limits

Color tags are intentionally unassigned for this regional umbrella; consult individual material records.

What we know—and what we don’t

Visual resemblance can narrow a comparison. Material identity, locality attribution and documented provenance need separate evidence.

C&C Reference Collection

Authenticated reference photography is still being assembled.

Sources & Further Reading
  1. USGS: McDermitt caldera

    2024 geological synthesis. Regional geology does not authenticate a traded slab.

  2. University of Nebraska–Lincoln historical agate database

    Saved institutional label/bibliography evidence; no image reuse permission inferred.

Historic locality information is not current collecting permission. For cutting, use suitable dust controls and material-specific safety guidance.