Is all sand the same?

We've been looking at sand! We wanted to know if all sand was the same. We looked at sand samples from Piha, Blockhouse Bay, Big Bay and Port Waikato.

We discovered a few things! 

- sand can be different colours.

- some sand has little shells in it, like sand from Blockhouse Bay.

- some sand is rough to touch, like the sand from Blockhouse Bay and Piha.

- some sand feels soft, like the sand from Port Waikato.

- some sand is magnetic, like the sand from Port Waikato. We know that magnets stick to metal, so we think there must be metal in the sand from Port Waikato. 

We have layered all the sand samples in a jar...we wonder if we can separate the Port Waikato sample from the other sand using a magnet?