Dallasite Jasper

Dallasite is a distinctive green, white, and black breccia found along the shores of Vancouver Island, British Columbia, often considered an unofficial provincial gemstone there. Though sold as a jasper, it is technically a volcanic breccia: angular fragments of altered basalt and other rock cemented together by silica (jasper and quartz) along with green epidote and chlorite.

The stone is named for the Dallas Road beaches of Victoria, BC, where it is commonly collected. Its mottled, patchwork look, deep greens against creamy whites with black flecks, makes each piece unique.

It is tough, takes a good polish, and is a favorite of Pacific Northwest rockhounds.

Dallasite formed in an oceanic volcanic setting. Submarine basaltic lavas and volcanic debris were broken into angular fragments, then later flooded by silica- and epidote-bearing hydrothermal fluids during low-grade metamorphism and alteration of the seafloor basalts.

These fluids deposited jasper, quartz, epidote (the green), and chlorite as cement and vein fillings between the rock fragments, welding the breccia into a hard, colorful mass. The green coloration largely comes from epidote and chlorite, while the white comes from quartz and feldspar-rich fragments and the black from iron-rich basaltic material.

Glacial and wave action later eroded these rocks, scattering tumbled pieces along Vancouver Island beaches where they are gathered today.

Identify Dallasite by its hallmark green-and-white patchwork with black or gray angular inclusions, an unmistakable brecciated, spotted look. It is hard (about 6-7) and takes a high polish.

The green is typically epidote/chlorite; the white is quartz/jasper cement. Unlike pure jasper, you can usually see distinct angular fragments rather than uniform color or smooth banding.

Look-alikes include unakite (pink feldspar plus green epidote, more pink than white) and various "ocean jaspers," which show round orbs rather than angular breccia fragments. Locality is a strong clue: classic Dallasite comes from Vancouver Island beaches.

Dallasite is used almost exclusively as a lapidary and collector stone. It is cut into cabochons, beads, spheres, and tumbled pieces, and is popular in regional jewelry and souvenirs from Vancouver Island.

Because it is tough and polishes well, it works for pendants, rings, and cabinet specimens. Its main value is its strong regional identity and attractive green-and-white patterning rather than precious-stone rarity.

In metaphysical circles it is associated with grounding and connection to nature, claims that are spiritual rather than scientific. Collectors prize beach-found, naturally tumbled pieces.