Agate
Banded chalcedony filling volcanic vesicles worldwide. Germany's Idar-Oberstein was the historic cutting capital; Brazil's Rio Grande do Sul and Uruguay now ship tons; Montana agates and Botswana gray banded remain collector favorites.
Known origins & mines
Ametista do Sul Geode Belt · Brazil
World amethyst capital: basalt lava-tube geodes up to cathedral size are mined by shaft here and in neighboring Iraí. Pale-violet with laven…
Idar-Oberstein Agate Town · Germany
500 years of agate cutting made Idar-Oberstein the world lapidary capital — local Nahe agates exhausted by 1800 forced Brazilian imports, cr…
Los Catalanes Agate Fields · Uruguay
Artigas department deposits bordering Brazil - Uruguay's banded agate capital, mined commercially since 1870.…
Soledade Agate Fields · Brazil
Basalt vesicle fields around Soledade ship thousands of tons of blue lace, moss and banded agate yearly — the volume heart of world agate co…
Lake Superior Agate Shores · United States
Ice-age glacial drift scattered Lake Superior banded agates across Minnesota beaches - the state gem, hunted by rockhounds for its red-orang…
Yellow River Montana Agates · United States
Ice-age Yellowstone flood gravels yield moss-and-dendritic agates glowing orange against black — rockhound gravel bars welcome public diggin…