In general, mineral particles are small, having formed within confined areas such as lava flows or between grains of sediments. Large crystals found in geodes and other rocks are relatively rare.

RENO, Nev. (KOLO) - The Reno-Sparks Convention Center (4590 S Virginia Street) is home this weekend to The Crystal Festival.

Ever wonder how Earth scientists examine rocks? We cut them up and throw them under a microscope ... and then everything ...

NASA’s Curiosity rover has uncovered intriguing traces of sulfur crystals embedded in Martian rock formations, adding weight ...

No bigger than a smartphone, this remarkable rock has layers that tell the story of the working lives and hardships of miners in the 1800s. A flawless blue topaz gemstone - the largest of its kind - ...

Silent auctions added an extra layer of excitement, as attendees placed their bids on rare and unique pieces, hoping to take ...

In his hand, he stroked a different rock — vanadinite, Dave said, joking about how hard it is to pronounce. It’s a lead-based mineral that forms reddish crystals, according to Dave.

PT Rocks and Gems, which offers crystals, stones, jewelry and decor ... who is also the tour director for the nonprofit ...

Curiosity rover cracked open a Martian rock, revealing a sight never before seen on Mars - a dazzling display of yellow ...

These minerals in turn may have spurred ... Using this ratio to calculate the ages of crystals within different layers of ancient rock, the researchers determined how the rock grew or eroded ...