The inside of an Agate stone found in the Rio Grande do Sul region of Brazil, surprised its finder because of its eerie resemblance to popular Cookie Monster character. Its owner, gemologist Lucas Fassari estimates the unusual gem is worth about $10,000.
“This is probably the most perfect Cookie Monster out there.”
The Agate stone contains brilliant blue quartz crystals with the wide eyes and big smile of the beloved Cookie Monster character from Sesame Street.
Agate is an often-colorful, banded volcanic rock formation consisting of chalcedony and quartz as its primary components. Agate minerals tend to from within pre-existing hollow rock. The cavity inside the hollow rock are caused by gases trapped inside the liquid volcanic material before the rock hardens. These cavities are then filled with silica fluids from the volcanic material.
Layers of silica are formed inside the rock beginning with the outermost “priming layer”. Layers continue to form, on atop another, alternating between bands of Chalcedony and crystalline quartz. Hollow areas, like the “eyes” and “mouth” of this Cookie Monster agate stone, are formed when the liquid silica does not completely fill the cavity.
Agate is named after the Achates River (now known as the Dirillo River) on the island of Sicily, Italy, whose upper waters were an ancient source of this gemstone.