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

This free course is available to start right now. Review the full course description and key learning outcomes and create an account and enrol if you want a free statement of participation.

Free course

An introduction to minerals and rocks under the microscope

3.7.3 Sulfides

Sulfur is an essential constituent of sulfide minerals, in which it commonly bonds with metals such as copper, lead and zinc. Sulfides can be important economically when they are concentrated in mineral deposits. They often occur as vein mineralisation, deposited by hot, watery fluids passing through fractures, fault zones and permeable rocks. Some are formed by segregation processes in sulfur-rich magmatic systems. Mining followed by smelting of the sulfide minerals allows the metals to be extracted. Examples of economically important sulfide mineral deposits include the Pb-Zn deposits of the Mississippi Valley and the vast disseminated Cu deposits of the Andes.

Pyrite (FeS2) (Figure 63a) is the most commonly encountered sulfide mineral in vein deposits and is also found in igneous, metamorphic and sedimentary rocks. Other common sulfide minerals in vein deposits include galena (PbS) (Figure 63b), sphalerite (ZnS) (Figure 15c) and chalcopyrite (CuFeS2).

Figure 63 (a) Pyrite (3 cm across). (b) Galena (7 cm across).

Take your learning further

Making the decision to study can be a big step, which is why you'll want a trusted University. The Open University has over 40 years’ experience delivering flexible learning and 170,000 students are studying with us right now. Take a look at all Open University courses.

If you are new to university level study, find out more about the types of qualifications we offer, including our entry level Access courses and Certificates.

Not ready for University study then browse over 900 free courses on OpenLearn and sign up to our newsletter 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 prospectus