Rock & Mineral Encyclopedia
Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.
Chalcedony
A waxy, translucent microcrystalline form of quartz that serves as the parent group for agate, jasper, carnelian, and onyx.
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Agate
A banded variety of chalcedony quartz, famed for its colorful concentric layers and enormous range of patterns and colors.
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Blue Chalcedony
A translucent, soft blue variety of microcrystalline quartz whose color comes from light scattering through its fine structure.
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Grape Agate
Clusters of tiny botryoidal chalcedony spheres resembling bunches of grapes, famously purple, found in Indonesia.
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Chrome Chalcedony
A vivid green chalcedony colored by chromium, often called mtorolite, resembling chrysoprase but owing its color to chromium rather than nickel.
gemstoneApricot Agate
A soft peachy-orange variety of banded chalcedony, naturally iron-tinted or dyed, popular for warm-toned beads and jewelry.
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Landscape Agate
A translucent chalcedony agate whose mineral inclusions form miniature scenes resembling mountains, trees, deserts, and skies.
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Seam Agate
Agate that forms in flat cracks or veins of host rock rather than rounded nodules, producing straight, parallel banding.
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Tube Agate
A chalcedony agate containing hollow or mineral-filled tubes that appear as rods, circles, or pipes depending on the angle of the cut.
gemstoneBamboo Agate
An agate whose layered, segmented banding resembles the jointed stalks and leaves of bamboo.
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Queensland Agate
Banded agate from Queensland, Australia, including the famous Agate Creek field, known for vivid fortification patterns.
gemstoneBahia Agate
A banded and plume agate from the Bahia state of Brazil, known for delicate dendritic and feathery inclusions.
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Green Agate
A green-hued banded chalcedony, ranging from natural soft greens to brightly dyed commercial stones.
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Plume Agate
A translucent agate containing delicate three-dimensional feather- or plant-like plumes of mineral inclusions suspended in chalcedony.
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Sweetwater Agate
A translucent Wyoming chalcedony filled with delicate black manganese dendrites that resemble tiny ferns, moss, or starbursts.
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Sagenite Agate
A chalcedony agate filled with radiating needle-like mineral inclusions, prized for its starburst and spray patterns.
gemstoneOrca Agate
A bold black-and-white banded chalcedony named for its orca-like coloring, popular as carvings and statement jewelry.
gemstoneRiband Agate
A banded chalcedony with straight, ribbon-like parallel layers, often cut across the bands for striking striped cabochons.
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Moss Agate
A translucent chalcedony filled with green or brown dendritic mineral inclusions that resemble moss, foliage, or landscapes.
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Black Agate
A deep black variety of banded chalcedony, often closely related to or treated like onyx, used for jewelry and carvings.
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Indian Agate
An affordable multicolored banded and mossy chalcedony from India, common in tumbled stones, beads, and meditation pieces.
gemstoneCarver Agate
A collectible Oregon plume and scenic agate with feathery red and gold inclusions suspended in translucent chalcedony.
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Flower Agate
A creamy pink-and-white chalcedony from Madagascar containing flower-like plume inclusions that resemble blossoms suspended in stone.
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Brecciated Agate
Agate that was shattered and naturally re-cemented by silica, creating a mosaic of angular fragments in a quartz matrix.
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