Royal Australian Chemical Institute NSW Branch presents

2021 RACI Crystal Growing Competition

Registrations are closed


Crystals are everywhere. Just think of our daily lives.Sugar and salt are crystals.  LCD computer and TV screens have many tiny crystals inside.

Where else can you find crystals? How about your classroom? If you enter the RACI NSW Crystal Growing Competition then you can create your own crystals within six weeks and then have a chance to have these crystals judged and entered into a National Competition organised by the Royal Australian Chemical Institute.

The process is safe and simple, and is designed to encourage students to develop an interest in Chemistry from a young age. Students can participate as individuals or with a friend, small groups or class groups. The competition is open to all students from Prep to Grade 12, in different categories. The competition is different for different age groups, with simple activities for early primary school involving easy to grow crystals with safe to handle substances and becoming more challenging. For examples, students in Grades 11 & 12 are invited to demonstrate their broader knowledge and grow more complex crystals, from any substance that can be safely sent through the mail.


Why be involved?
Do you want to have fun with Science? Would you like to do some simple chemistry experiments with your students? Then enter the RACI NSW Crystal Growing Competition and learn all about growing beautiful crystals.

Participation assists students to develop skills in applying the processes of Working Scientifically as part of the NSW syllabus aims. It provides a learning experience which allows students to acquire scientific knowledge and skills and develop understanding about phenomena within and beyond their experience. And it is fun to do!


What’s involved?
The aim is to grow the best single crystal of potash alum (also called alum or potassium aluminum sulfate) or another substance over a period of 3 - 6 weeks during Term 2 so it is important to begin your experiments early enough to allow time for your crystals to develop. With simple kitchen items, students can grow their first seed crystal and then with time and patience watch it growing. 
Crystals can be grown by one student or by a group of up to four students in the classroom, as part of a science club, or at home. A class group may also enter however the Certificate will be issued for the Class name only

Crystals will be judged on shape and clarity firstly, rather than size. The winning crystals in each division will receive PDF certificates and winning schools receive a trophy. The best crystals will be sent to the RACI National Competition.

The competition is judged in the following categories:

  • Alum only: K-3 / Years 4-6 / Years 7-8 / Years 9-12
  • Open (anything other than pure alum): Primary (K-Year 6) / Secondary (Years 7-12)

*A good example for Open  category substance would be copper sulfate, which makes a lovely blue crystal. Please note that  food dye shouldn't be added to alum to make coloured crystals.  The colouring goes into the crystal in a really blotchy way and makes them opaque and cloudy-looking.


How do you enter?

1. Purchase alum directly from Rowe Scientific if needed. 

The direct contact person for NSW/ACT orders is: Kazi Hoque ([email protected], ph: 02 9603 1205).

Please send your orders directly to Kazi using the order form, and cc in  [email protected]

Rowe Catalogue Number CA3524 ALUMINIUM POTASSIUM SULFATE DODECAHYDRATE (GLR) @ $21.50 per 500g, excluding GST.


2Grow your crystals individually or as a group during Term 2. (No registration is required at this stage)

3. When you are ready to mail the crystals, register/pay online by Friday 25 June 2021.

The student details form must be completed and returned to [email protected]

*Costs: Registration $16.5 per school,  $5.50 per crystal (inc GST)


3. Send your crystals to NSW Branch Office - RG03 Dalton Building, UNSW Kensington Campus, NSW 2052 Australia by Friday 9 July 2021.


How do you grow good crystals?