An overview of vis-nir-swir field spectroscopy - Spectral International

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Advanced Argillic
This is an intense alteration phase, often in the upper part of porphyry systems.
It can also form envelopes around pyrite-rich veins that cross cut other alteration
types. The minerals associated with this type are higher temperature and include
pyrophyllite, quartz, andalusite, diaspore, corundum, alunite, topaz, tourmaline,
dumortierite, pyrite, and hematite.
Propylitic
Forms the outermost alteration zone at intermedite to deep levels in the porphyry
system. It can be mineralogically zoned from inner actinolite-rich to out epidote
rich facies. chlorite, epidote, albite, calcite, actinolite, illite, clay pyrite
Figure 41 - Propylitic alteration for porphyry systems
includes; Fe- chlorite, Mg-chlorite, epidote, actinolite,
calcite, illite, montmorillonite, albite, and pyrite.
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Figure 42 - Copper carbonates in porphyry
systems can include azurite, malachite,
aurichalcite, and rosasite.