Crystals are all around us, but we just might not know where to look. Come and learn about what crystals are, how they are formed, and natural and man-made examples of this amazing substance.

What are Crystals?

When you hear the word crystal, what do you think of? When many people think about crystals, they might think of fancy, sparkly objects like a crystal vase or crystal glassware. While some crystals are this way, this isn’t the case for all of them. Crystals are actually all around you, and you probably don’t even realize it. Crystals are just solid forms of matter that have a pattern in their geometric structures, like 3-D shapes. Some crystals are cubes, while others might form as a rectangular prism or a three-dimensional hexagon. Regardless of the 3-D shape, crystals have flat, smooth planes known as faces.

1. Main points:

Crystals are solid forms of matter with specific geometric structures and patterns. They can take various 3-D shapes like cubes, rectangular prisms, or hexagons, and have distinctive flat, smooth surfaces called faces.

2. Questions:

• Content Analysis: What are the common shapes that crystals can form?
• Linguistic Analysis: How does the text challenge the common perception of crystals?
• Thematic Analysis: What key characteristic defines a crystal, according to the text?

3. Further Discussion:

• If you could create a new type of crystal, what shape would it be and why?

4. Answers:

• Content Analysis: Crystals can form in shapes like "cubes, rectangular prisms, or three-dimensional hexagons."
• Linguistic Analysis: The text challenges the perception by stating, "While some crystals are this way, this isn’t the case for all of them."
• Thematic Analysis: The defining characteristic of a crystal is "solid forms of matter that have a pattern in their geometric structures."

Think about the different shapes crystals can take. Isn’t it fascinating how nature forms such perfect shapes? What’s the most interesting crystal shape you’ve heard of or seen?

How are Crystals Formed?

Molten rock

There are many different ways that a crystal can be formed, both in nature and man-made. However, the different processes all have the same basic concepts. To make a crystal, you will need a hot substance. Next, the substance needs to cool down and become a solid. In nature, crystals might result from the cooling of molten rock, which is the solid form of lava from a volcano that comes from deep inside the Earth’s core. The minerals in the molten rock grow into a crystal. This process is known as crystallization.

While this is one way that crystals form, you don’t necessarily need molten rock to create a crystal. In fact, you can build crystals yourself with just a few simple ingredients: Epsom salt, hot water, and a small bowl. First, you put the salt and water in the bowl and stir the solution until the salt has dissolved. Next, you put the bowl in the refrigerator for a few hours. This will allow the water to cool so that the minerals, which in this case is the Epsom salt, can crystallize. During this process, the atoms in the minerals begin to stick together and form 3-D patterns. Last, you remove the cooled solution from the refrigerator and scoop out the crystals. You could even add food coloring to jazz it up a bit and get some beautiful, colorful crystals.

1. Main points:

Crystals can form naturally from cooling molten rock, a process called crystallization, or through man-made methods like mixing Epsom salt with hot water and cooling it, allowing atoms in the minerals to form 3-D patterns.

2. Questions:

• Content Analysis: What are the basic steps involved in forming a crystal?
• Contextual Analysis: How does the process of crystallization occur in nature?
• Thematic Analysis: What is an example of a man-made method for creating crystals?

3. Further Discussion:

• If you could grow your own crystal, what color would you choose and why?

4. Answers:

• Content Analysis: "You will need a hot substance…cool down and become a solid."
• Contextual Analysis: "Crystals might result from the cooling of molten rock…the minerals in the molten rock grow into a crystal."
• Thematic Analysis: "You can build crystals…with Epsom salt, hot water, and a small bowl."

Imagine the countless shapes and colors of crystals you could create. What do you think makes the process of growing crystals so fascinating?

Crystals in Nature

Snowflakes are crystals.

Have you ever been on a crystal hunt? It isn’t as hard as it seems, as there are many different forms of crystals in nature. For example, snowflakes are examples of crystals, as they are crystallized ice. While all snowflakes might look like simple, round shapes as they fall from the sky, they actually have different geometric patterns. In fact, every single snowflake has a unique structure that is different than the rest.

Another popular crystal that is found in nature is called a gemstone, which is a precious stone like a ruby, diamond or quartz. Gemstones are often used in jewelry and can be very expensive. In fact, there is a rare form of red diamond that will cost you around $1 million per carat!

1. Main points:

Snowflakes and gemstones are both examples of natural crystals. Snowflakes are crystallized ice with unique geometric patterns, while gemstones like rubies, diamonds, and quartz are precious stones often used in jewelry, with some, like red diamonds, being extremely valuable.

2. Questions:

• Content Analysis: What are two examples of crystals found in nature?
• Contextual Analysis: How is each snowflake’s structure unique?
• Socio-cultural Analysis: Why might gemstones like red diamonds be so valuable?

3. Further Discussion:

• If you could design your own unique snowflake, what pattern would it have?

4. Answers:

• Content Analysis: "Snowflakes…crystallized ice" and "gemstone, which is a precious stone like a ruby, diamond or quartz."
• Contextual Analysis: "Every single snowflake has a unique structure that is different than the rest."
• Socio-cultural Analysis: The text doesn’t directly address this, but it implies that rarity and beauty contribute to the high value of gemstones like red diamonds.

Think about how special each snowflake is with its own design, just like every person is unique in their own way. What do you think makes each snowflake different from the others?

Man-made Crystals

Rock candy

Think about the food that you ate over the past week. Did you have any crystals to eat for breakfast, lunch or dinner? This isn’t as crazy of a question as it seems. There are many forms of edible crystals, such as table salt, sugar, or one of my favorites – rock candy! Crystals are also found in pencils, as the graphite used in lead is made up of crystals. Are you reading this lesson on a computer screen? Well, the person who made your computer screen used liquid crystals in the monitor. Pretty cool, huh?

1. Main points:

Edible crystals like table salt, sugar, and rock candy are common in our diets. Crystals are also present in everyday items like pencils (graphite) and computer screens, which use liquid crystals.

2. Questions:

• Content Analysis: What are some examples of edible crystals?
• Thematic Analysis: How are crystals used in everyday objects like pencils and computer screens?
• Socio-cultural Analysis: Why do you think people enjoy eating rock candy?

3. Further Discussion:

• If you could invent a new use for crystals, what would it be and why?

4. Answers:

• Content Analysis: "Edible crystals, such as table salt, sugar, or…rock candy."
• Thematic Analysis: "Crystals are also found in pencils, as the graphite used in lead is made up of crystals…liquid crystals in the [computer] monitor."
• Socio-cultural Analysis: The text doesn’t directly answer this, but it suggests that the novelty and sweetness of rock candy make it enjoyable to eat.

Isn’t it surprising how crystals are a part of so many things we use every day? If you could make a crystal out of anything, what would you choose and how would you use it?

Lesson Summary

Crystals are all around you in many different forms, such as gemstones, salt, and even in your computer screen. There are many ways that crystals are formed, such as the cooling of molten rock. See how many crystals you can spot this week – there will probably be more than you think!