Sorting our Rock Samples

It is soft and crumbly when you ...

Look how hard it is when you ....

Have you tried shining a light through it?

The samples in the pictures are - ROCK CRYSTAL, PYRITE (fool's gold) and

the mineral rose quartz in its natural and polished state

We spent time this afternoon trying to identify our great collection of rock and mineral samples.

Some we recognised easily e.g. granite and sandstone.

St. Magnus Cathedral is a famous example of a red sandstone building.

Others we had never heard of e.g. obsidian and basalt.

Firstly, we sorted the rock samples by their rock type.

IGNEOUS SEDIMENTARY METAMORPHIC

To find out more about how these different rocks were created click on the Rock Hounds homework link where you will find an animation explaining how each type of rock was formed.

We then attempted to sort a few of the easier samples by property e.g. How hard is it?.

We found that marble and granite were very hard but sandstone and chalk were quite soft.

We know that granite and marble are used in buildings.

Aberdeen is called the 'Granite City' because so many of the buildings there are made of granite.

Granite is an example of an igneous rock. Granite is the signature rock of Planet Earth. Other rocky planets such as Mars, Venus and Mercury are covered with basalt, as is our ocean floor.

Try out our 'Who Am I'? rock quiz on the homework link. It is VERY tricky!

Our next task will be to show how igneous rocks can be grainy and made of large crystals or smooth and glassy.

We will be melting sugar to ... follow our blog to find out what happens next...