Why is a ruby red and a sapphire blue if both are the same mineral?

What Crafty Clover says in this video

Intro

Hi there, curious minds! I'm Crafty Clover! Let's discover something amazing. Why is a ruby red and a sapphire blue if both are the same mineral?

The Big Idea

Rubies are red. Sapphires are blue. But they're the same mineral!

Corundum

Step one: Corundum. Rubies and sapphires are both made of corundum, a very hard mineral made of aluminum and oxygen. Pure corundum is clear.

Tiny Traces

Step two: Tiny Traces. A tiny bit of chromium turns corundum red and makes a ruby. Traces of iron and titanium make it blue.

Many Colors

Step three: Many Colors. Sapphires can also be yellow, pink, or green. Small amounts of other elements can make a big difference in color.

A Closer Look

Let's take a closer look! Pure is clear. Chromium makes red. Iron makes blue. Sapphires vary.

Quick Facts

Quick facts! Corundum is number 9 on the Mohs scale. Chromium makes ruby red. Iron makes sapphire blue. Pure corundum is clear.

Think Like a Scientist

Now, think like a scientist! Fill a glass with clear water. Add one drop of food coloring. Watch it spread. How does a little color change the whole glass? How is this like rubies?

Outro

Rubies and sapphires are both corundum, made of aluminum and oxygen. A tiny bit of chromium makes red ruby, while iron and titanium make blue sapphire. A little can change a lot! Nature is a great artist. Science is amazing! Keep wondering and keep exploring! Share what you learned with someone at home, and see what they think! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!