Carey Plume Agate

Carey plume agate is a collectible plume agate found near the town of Carey in south-central Idaho. It is sought after for its vivid, feather-like plumes, often in red, pink, black and golden tones, suspended in a translucent to milky chalcedony base.

Like other plume agates it is a microcrystalline quartz (chalcedony) whose appeal comes from three-dimensional mineral growths that resemble feathers, ferns or flowers floating inside clear stone. Each piece is unique, and well-formed scenic plumes are highly prized.

Its scarcity and striking patterns make it a favorite among American agate collectors and high-end cabbers.

Carey plume agate formed in gas cavities, seams and fractures within the volcanic rocks of south-central Idaho. Silica-rich groundwater filled these voids and began depositing chalcedony.

While the silica was still a soft gel, iron- and manganese-bearing solutions infiltrated and crystallized into three-dimensional, branching plumes. Continued deposition of clear silica then encased the plumes, freezing them in place within the agate.

Iron oxides produced the red and pink plumes, while manganese contributed darker black growths. Subsequent uplift and weathering exposed the agate-bearing host rock, where it is collected near Carey.

Look for translucent to milky chalcedony containing soft, three-dimensional plumes in red, pink, black or gold that appear to float inside the stone; the billowy plume habit is the key trait.

Hardness is 6.5-7, with a waxy to vitreous luster, white streak and conchoidal fracture.

Look-alikes: Priday plume agate from Oregon is very similar, distinguished mainly by locality and color mix; dendritic agate shows flat, two-dimensional ferns rather than rounded plumes; moss agate has greener, tangled inclusions; sagenite agate has needle-like sprays. The vivid red-pink plumes and Idaho origin point to Carey.

Carey plume agate is a premium cabbing and collecting material, cut into cabochons, slabs and display pieces that highlight the floating plumes. Scenic, well-defined specimens can command high prices.

It polishes well and is durable enough for pendants, rings and bolo ties. Collectors prize rough and finished pieces alike for their unique plume scenes.

Metaphysically, plume agates are linked to growth, vitality and a connection with nature, though these associations are traditional rather than scientifically supported.