Simple compounds. Unusual mineral occurrences
2004; Multidisciplinary Digital Publishing Institute; Linguagem: Inglês
10.1017/cbo9780511811296.022
ISSN2075-163X
AutoresHans‐Rudolf Wenk, Andrey Bulakh,
Tópico(s)Radioactive element chemistry and processing
ResumoAfter the discussion of some of the most common but also the most complex minerals in Chapter 19, we now examine some structurally and chemically very simple compounds that are rare and form only under unusual conditions. In this chapter we discuss minerals of native elements such as graphite (C), diamond (C), copper (Cu), gold (Au) and silver (Ag) and solid solutions of these elements (for instance, Au–Ag and Au–Cu) (Table 20.1). There are also intermetallic compounds with ordered crystal structures that differ from the end members. Often, these intermetallic compounds form during cooling as a result of ordering of high-temperature solid solutions of the same compositions. Some naturally occurring examples of intermetallics are awaruite (FeNi3), wairauite (FeCo), isoferroplatinum (cubic Pt3Fe), tetraferroplatinum (tetragonal PtFe), tulameenite (Pt2FeCu), ferronickelplatinum (Pt2NiFe), hongshiite (PtCu), rustenburgite (Pt3Sn), urvantsevite (PdBi2), auricuprite (Cu3Au), and schachnerite (AgHg). Don't be intimidated – no one will expect you to memorize these names and formulas. They are listed merely to give you an impression of the astonishing variety of intermetallic compounds.
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