PHOTOS: Nyssa’s Thunderegg Days rock tours are a hidden gem

One of the rock enthusiasts on Nyssa's Thunderegg Days rockhound tour split open a seemingly simple rock to find an agate. Each ring in the agate indicates a different "blurb" of water carrying various minerals that affect the color, according to rock tour leader William Nance. (The Enterprise/Isabella Garcia)

NYSSA — Nyssa's three-day Thunderegg Days celebration is full of community events, local vendors and, for those who want to explore off the beaten path, rockhound tours.

While thundereggs, a type of rock formation made exclusively through rhyolite lava, are abundant in the hills surrounding Nyssa, tour-goers can find opal, agate and other colorful mineral deposits. The first of two rockhound tours, led by archeologist and geologist William Nance, attracted a small group of six rock enthusiasts to rhyolite lava calderas and beach strands in the . . .