Why Do Some Rocks Have Sparkly Crystals Inside? | RapidSmartFacts

Some ordinary-looking rocks crack open to reveal bright, glittering crystals inside. But how do

those crystals grow there? It starts with a hollow space inside the rock,

often created by gas bubbles in molten lava. When the lava cools,

that bubble becomes an empty chamber. Over time, mineral-rich water seeps into the cavity

through tiny cracks. These minerals, like quartz, amethyst, or calcite,

dissolve in the water. As the water slowly evaporates, the minerals begin

to crystallize. The longer the water stays trapped, the larger the crystals become.

Each mineral grows in its own geometric pattern, creating those sharp, sparkly shapes.