12
3
LAB
GEMMY GOODNESS
MATERIALS
•
1
⁄
2
cup (120 ml) of very hot water
(boiling is okay but not required)
• 2 clean, 1 quart (946 ml), narrow-
mouth glass Mason jars
• 2
1
⁄
2
tablespoons (45 g) of pure
alum powder (potassium aluminum
sulfate—you must have the right kind!)
• Metal stirring spoon
• Paper towel
• Rubber band
• 12" (30 cm) of light nylon fishing line
• Scissors
• Ruler, pencil, or single chopstick
PROTOCOL
STEP 1:
Add
1
⁄
2
cup (120 ml) of hot water
to a clean jar.
STEP 2:
Slowly stir in the alum with the
metal spoon. Add as much alum as you
can until it starts to pile up on the bottom
of the jar. This means your solution is
saturated.
STEP 3:
Cover the jar with the paper
towel and use the rubber band to keep it
in place. This keeps dust out of your alum
solution and prevents impurities from
wrecking your crystal structure.
STEP 4:
Let sit overnight (sixteen hours
minimum).
STEP 5:
Pour the contents of the first
jar into the second clean jar, leaving the
residue in the first jar. Inspect this residue
closely. These are small “seed” crystals
that you’re going to need to create a
larger crystal, so make sure they are large
enough to work with. If not, return the
solution to the jar and wait another day.
STEP 6:
Use the light nylon fishing line to
tie a knot around the largest seed crystal.
Do not damage the crystal. If it is too
small, return to step 5 and get a larger
seed crystal to work with. The more per-
fect your seed crystal, the better your end
crystal will look.
Grow your own perfect
alum crystal, ready for
shaping into homemade
earrings or bracelets.
Safety Tips
- Ask an adult for help boiling
the water.
- Avoid getting the alum in your
eyes. If you do, rinse them with
cold water.
