Ice Crystals
Water molecules form a hexagonal lattice shape known as an ice crystal. Ice crystals form when a single droplet of water freezes while other water droplets condense on the surface of the frozen water droplet. This occurs most frequently in clouds. The process forms what is known as a snowflake. A snowflake is a cluster or group of ice crystals. The ice crystals fall, frozen, from the cloud and group together to create a beautiful scenery where they land.
Stalagmites and Stalactites
In most, if not all, caverns exist ancient geological formations called stalagmites and stalactites. These structures are also known as speleothems of which calcite crystals compose a majority. Acidic water seeps through fissures and cracks in the earth above the caverns, dissolving the calcite from the limestone and precipitating it as the water drips from the cavern ceiling. In natural caves, stalagmites grow approximately an inch (or 29 mm) in 27 years.
Mineral Crystals
Mineral crystals are the most commonly considered form of crystals. Walk into a jewelry store and you will find some of the most precious, and expensive, crystals known. These crystals come in two different forms: isometric and nonisometric. There are 15 isometric forms and 32 nonisometric forms, which creates an issue when trying to make a distinction without a proper guide. Examples of mineral crystals include the common quartz, rubies, diamonds and iron pyrite (fool's gold).
Uses for Natural Crystals
Crystals found in nature have many uses. The most commonly thought of use is fashion. Jewelry, large and small, utilize the crystals found in nature. Another common use of the crystal is entertainment and tourism. The monumental geological formations generate tourism and revenue from the curious and the knowledgeable. The ice crystals found in snowflakes make for hours of fun and entertainment for families. Snowmen, snow forts, and snowball fights are only a few examples of common activities surrounding the ice crystals.