Become an Arenophile - Start collecting sand... It's dinolite- addictive!

Go treasure hunting in the sand samples, piece together some molecules to discover why crystals are the shapes they are, make your own set

of crystal models out of paper...


The sand samples


Students embarking on a treasure hunt....


Garnets galore!


Crystal building resources in the Allen Centre


Noah's crystal of calcite


Robbie and Toby build pyroxene with a chain

of silicon dioxide molecules

Below are dinolite photographs of sand grains in the sand sample collected from Sandfly Bay on the Otago Peninsula.

Discover red garnets, transparent rock crystal, banded agates, flakes of mica, fragments of hornblende and pyroxene as well as tiny pieces

of polished shell. Scroll down to identify the grains...

Except for the quartz sand grains (bottom left) which have been magnified 50X, the grains have been magnified 200X. Simply STUNNING!

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Some crystals to look for in your sand specimens:

These crystals are rock-forming minerals and become grains of sand when the rock weathers and breaks down.

The grains can appear brightly coloured because their surfaces have been polished by rolling around in rivers and the sea.

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Olivine - olive green


Garnet - mostly pink, orange or red.


Quartz - transparent

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Mica/Muscovite - transparent flakes

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Hornblende - shiny black

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Feldspar - pink, white or red


Pyroxene - dark black


Plagioclase - white


Magnetite - dark grey-black


Epidote - lime green


Mica/Biotite - shiny black flakes


Hematite - reddish brown; often seen as

brown stains on other rocks.

Colours of Quartz...

Quartz occurs in many colours. The colours are caused by traces of different elements. Here are some examples...

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Element: Manganese

Rose Quartz

Elements: Titanium or Manganese


Element: Iron

Rock Crystal

Colourless - No trace of elements

All about crystals:

mineralogy for kids.pngFor Senior students...

Click the picture to discover all about crystals...

or visit Crystal City


Click the dodecahedron

to make a paper garnet crystal.

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Click the book cover to see the amazing sand

grain micro-photography of Dr. Gary Greenberg.

sand atlas2.jpg Click the image to explore the Sand Atlas

crystalshapes250pix.jpgClick the image to print out the templates to

cut-and assemble your own mineral crystal shapes.


Click on the image to grow your own crystals


Build a calcite crystal out of polystyrene balls.

In this model: CaCO³Calcium (Ca) - white

Carbon (C) - black

Oxygen (O) - red

Click image to "Make Five"A Chemical Formula Game

6opal023.jpgWhat is a Crystal?

Click Opal's Pals to find out...




Go Microfossil-huntingin the North Otago Greensand...

Microfossils to look for in the North Otago Greensand Sample...

Look for skeleton fragments of foraminifera, ostracods, and coccoliths which sunk to the sea floor 25 million years ago.

The green-blue colour of the sand is caused by the green clay mineral glauconite.


Handy tip...

Most of the fossils are broken into tiny pieces - search for bits of skeleton which help you

to identify the whole organism.

You willl find them more easily if you use the dinolite microscope at its 200X magnification.


Coccoliths are tiny round, plates of calcium

carbonate, arranged in a circle and part of

the bodies of single-celled algae.


Ostracods are tiny seed shrimps with their bodies

enclosed in a bivalve shell.

Foramenifera ("hole-bearers") or forams for short,

are tiny single-celled animals with intricate shells

made up of chambers, each chamber linked by a hole.