An introduction to minerals and rocks under the microscope
An introduction to minerals and rocks under the microscope

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.

Free course

An introduction to minerals and rocks under the microscope

1.8 Learning outcomes for Section 1

Now you have completed this section, you should be able to:

  • give, with an appropriate example, the meaning of the terms phase, phase boundary, and phase transformation, and interpret stability fields in terms of pressures and/or temperatures, using a phase diagram
  • describe and recognise, giving examples, various physical properties of minerals, including lustre, cleavage, hardness and density
  • describe, giving mineral examples, the main differences between metallic, ionic and covalent structures, and their type of bonding
  • explain the significance of various types of defects in crystals
  • explain the meaning of the terms lattice, unit cell, reflection and rotational symmetry, and how these relate to crystal systems.

Now try the following questions to test your understanding of Section 1.


Using the phase diagram illustrated in Figure 4, determine: (a) the pressure at which water would boil at a temperature of 50 °C; and (b) the pressure and temperature at which solid ice, liquid water and gaseous steam could coexist.


On testing, an unidentified mineral was found to scratch window glass, but was itself scratched by a hardened steel file. What is the hardness of this mineral?


Take your learning further371

Making the decision to study can be a big step, which is why you'll want a trusted University. The Open University has 50 years’ experience delivering flexible learning and 170,000 students are studying with us right now. Take a look at all Open University courses372.

If you are new to university level study, we offer two introductory routes to our qualifications. Find out Where to take your learning next?373 You could either choose to start with an Access courses374or an open box module, which allows you to count your previous learning towards an Open University qualification.

Not ready for University study then browse over 1000 free courses on OpenLearn375 and sign up to our newsletter376 to hear about new free courses as they are released.

Every year, thousands of students decide to study with The Open University. With over 120 qualifications, we’ve got the right course for you.

Request an Open University prospectus371