What is a streak test?

What Crafty Clover says in this video

Intro

Hi there, curious minds! I'm Crafty Clover! Let's discover something amazing. What is a streak test?

The Big Idea

A mineral's outside color can trick you. But its powder tells the truth! That's the streak test.

The Test

Step one: The Test. A streak test rubs a mineral across a rough, white, unglazed porcelain tile to leave a line of powder. The color of the powder can be different from the color of the mineral.

Surprises

Step two: Surprises. Hematite looks silver or black but leaves a reddish-brown streak. Pyrite leaves a greenish-black one.

Reliable

Step three: Reliable. Streak color is often more reliable than the outside color for identifying minerals. Rock detectives use it all the time.

A Closer Look

Let's take a closer look! Tiles are rough. Hematite is silvery. Pyrite is brassy. Streaks reveal truth.

Quick Facts

Quick facts! A streak tile can be a piece of the back of a bathroom tile. Hematite streaks red-brown. Pyrite streaks greenish-black. Streaks beat outside color.

Think Like a Scientist

Now, think like a scientist! Find an unglazed tile. Rub chalk on it. Rub a crayon and a pencil next to it. Compare each streak with its color. Which streak surprised you?

Outro

A streak test rubs a mineral across a rough white tile to leave a line of powder. The powder color can differ from the outside, like silvery hematite leaving a reddish-brown streak. It's a reliable clue! Science is amazing! The world is full of surprises. Keep asking big questions, and keep exploring with me! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!