W036 / Oregon

Opal Butte opal

Natural opal; several appearances and stability classes

Opal Butte produced several kinds of opal. Colorful flashes, clear material and opaque color are not all the same optical effect.

← Western Lapidary Materials
Reference photograph pending

What it is

Natural opal; several appearances and stability classes

What to look for

Compare clarity, body color and play-of-color separately. Dendritic patterns may occur; not every piece is precious opal.

At the cutting bench

Stability differs between pieces. Inspect crazing and obtain material-specific cutting and storage advice before processing inherited rough.

Under the loupe

Similar-looking opal from elsewhere cannot establish this source. “Rainbow” in older writing should be read in context, not assumed equivalent to modern seller terminology.

Source & collecting access

Historical production is documented; present mine access and production quantity are unknown in this record. No public-dig permission is implied.

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

The 1988 study describes opal in rhyolite geodes within altered perlite. Its varied sample descriptions should not be treated as a guarantee for unlabelled material.

Collecting & trade context

An older Opal Butte label is worth preserving, especially when a piece looks unlike familiar Australian or Ethiopian opal.

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

White/Cream/Clear, Blue, Red, Yellow, Multicolor

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. Kevin Lane Smith: Opals from Opal Butte, Oregon

    1988 gemological study; stability varies and historical mining is not present permission.

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