A sugar molecule contains 12 carbon atoms, 22 hydrogen atoms and 11 oxygen atoms (or as chemists say, sucrose is C12H22O11). If you make some sugar syrup (a concentrated solution), and leave it for a few days on a dish in the open, crystals will form.
More sugar
dissolves in warm water, so you need access to the kitchen, a bowl, some hot
water (60ºC, which is not too hot to touch), two spoons, a glass bowl, a glass
dish and some sugar. Put the water into the bowl, add sugar with a dry spoon,
and use the second spoon to stir it until the sugar is all dissolved. Use the
dry spoon to add more sugar, and keep going until no more sugar will dissolve.
You have just made syrup.
Then carefully
pour some of the syrup into the dish, leaving the last solid crystals in the
bowl, and put it somewhere safe (from pets, careless adults and curious smaller
children) for a few days.
You should get solid crystals like the first two. Use a magnifying glass to compare the crystals you have made with the crystals in the sugar container. They should look the same, but they probably won’t. I think I know why, but maybe I don’t. Over to you!
Borax
crystals
You will find borax in the supermarket, in the laundry
products aisle. When you buy it, you will see that it is not labelled as a
poison, though it has a label saying ‘Keep out of reach of children’. While
borax is not extremely poisonous, 5
or 6 grams of it could kill a baby, and the powder or a solution could burn
your eyes, so be careful handling it. Common sense is all you need, and the
crystals are pretty and easy to grow.
You only need a
small amount of borax, about as much as would cover a $2 coin with 2 mm of the
powder (use an old teaspoon and wash it afterwards). You also need a small dish
(I used a Petri dish) and some hot water. I also used an old plate and a
microwave oven. Put the borax in the Petri dish, add some hot water, and stir
the borax in.
If the borax all
dissolves, add a little bit more borax, and when no more will dissolve, add
some extra water and stir it all in. You don’t need to be precise here, because
if the borax solution isn’t saturated, it will become saturated as water
evaporates. After a couple of days, crystals start to grow (or after an hour,
if you leave the dish in the sun on a sheet of black paper).
Granite
crystals
The word ‘granite’ means different things to different people.
To a poet, any hard rock is granite, and a stone mason calls any rock with
visible crystals granite, but geologists divide those big-crystal rocks up into
granite, granodiorite, diorite, gabbro and others (and the poet’s granite and
what the mason calls granite may not even be granite at all!).
A granite hand
specimen with a blown-up inset, and a small portion of a huge granite sculpture
in Vigeland Park, Oslo, Norway.
Granite cools slowly enough for big mineral crystals to
form, far below the earth’s surface, and it only shows up on the surface when
it is uncovered by weathering and erosion. Basalt is a rock that cools very
fast, so any crystals that form are too tiny to see.
Some crystal thoughts
The study of crystals is either crystallography, or
gullibility if you have some theory that crystals have some magical power to
cure illness. Crystals do indeed have an amazing healing property, but only for
the sick wallets of crystal sellers, and crystals have also been used to
resuscitate dying bank balances.
The tagline “A
diamond is forever…” was coined by Frances Gerety, for a de Beers’
advertisements in 1947, but diamonds are just hard crystals, and way back in
1772, chemist Antoine Lavoisier showed that a diamond would burn, if he heated
it enough. In case you want to try this, Lavoisier sealed his diamond in a
glass container and used a strong lens to focus the sun’s heat on his target.
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