Minerals and the crystalline state: Figure 7 Some coloured varieties of quartz: (a) purple amethyst (crystals 1.5 cm long); (b) grey smoky quartz (5 cm long); (c) pink rose quartz (8.5 cm long).

My OpenLearn Profile

Personalise your OpenLearn profile, save your favourite content and get recognition for your learning

Create account / Sign in

Course content Course content

Minerals and the crystalline state

Start this free course now. Just create an account and sign in. Enrol and complete the course for a free statement of participation or digital badge if available.

More free courses

Figure 7 Some coloured varieties of quartz: (a) purple amethyst (crystals 1.5 cm long); (b) grey smoky quartz (5 cm long); (c) pink rose quartz (8.5 cm long).

3.2 Colour

Take your learning further

Making the decision to study can be a big step, which is why you’ll want a trusted University. We’ve pioneered distance learning for over 50 years, bringing university to you wherever you are so you can fit study around your life. Take a look at all Open University courses.

If you’re new to university-level study, read our guide on Where to take your learning next, or find out more about the types of qualifications we offer including entry level Access modules, Certificates, and Short Courses.

Want to achieve your ambition? Study with us and you’ll be joining over 2 million students who’ve achieved their career and personal goals with The Open University.

Browse all Open University courses

My OpenLearn Profile

About this free course

Become an OU student

Download this course

Share this free course