1. PORPHYRY COPPER
ALTERATION

2. Howell

4. Figure 1A: Schematic illustration of alteration zoning and overprinting relationships in a calc-alkalic porphyry system.
Mineralization occurs in potassically altered intrusions and adjacent wallrocks. Three propylitic alteration subfacies (actinolite, epidote and chlorite zones) can occur around the potassic-altered rocks. In this example, the porphyry has been partially overprinted by a lithocap (silicic and advanced argillic alteration assemblages) that contains a domain of high sulfidation epithermal mineralization. The roots of the lithocap can produce a pyrite halo to the porphyry system.
The degree of superposition of the lithocap into the porphyry system is contingent on uplift and erosion rates at the time of mineralization. B: Schematic illustration of alteration zoning and overprinting relationships in an alkalic porphyry system, based on geological relationships from the Cadia East
porphyry Cu-Au deposit (Tedder et al., 2001; Wilson 2003; Cooke et al., 2007). The alkalic equivalent of a lithocap contains less acidic alteration assemblages (albite – sericite – K-feldspar). The propylitic sub-facies are more complicated than in the calc-alkalic example, and calcium-bearing alteration minerals (calcite, actinolite, epidote, garnet) occur in the core of the deposit, in contrast to calc-alkalic porphyries.
Inspirations for this diagram came from Sillitoe and Thompson (2006). Abbreviations: ab – albite; act – actinolite; anh – anhydrite; Au- gold; bi – biotite; bn – bornite; cb –
carbonate; chl – chlorite; cp – chalcopyrite; epi – epidote; gt – garnet; hm – hematite; Kf – K-feldspar; lm – laumontite; mt – magnetite; pr – prehnite; py – pyrite; qz – quartz; ser – sericite; tm – tourmaline.
Proceedings of Exploration 07: Fifth Decennial International Conference on Mineral Exploration" edited by B. Milkereit, 2007, p Advances in Geological Models and Exploration Methods for Copper ± Gold Porphyry Deposits Holliday, J. R. [1], Cooke, D. R. [2]

5. Schematic diagram of generalized alteration zones within porphyry copper systems. (Sillitoe, 2010).

6. Agus, 2011

9. MORENCI, AZ

10. PORPHYRY COPPER ALTERATION
ALTERATION ZONES BY ROCK TYPE
INTRUSIONS
CENTRAL CORE = K-SILICATE ZONE - POTASSIC
BIOTITE +/- K-SPAR
INTERMEDIATE – “SERICITE” ZONE - PHYLLIC
QUARTZ + CHLORITE
OVERPRINXXTED BY “SERICITE” + PYRITE
WALL ROCKS - FURTHER FROM INTRUSION
PROPHYLITIC ZONE
EPIDOTE, CHLORITE, ALBITE
LEACHED CAP
ADVANCED ARGILLIC ALTERATION
PRODUCT OF ACID WATER LEACH FORMED BY ABSORPTION OF MAGNETIC VAPOR INTO METEORIC WATER

11. ALTERATION MINERALS PORPHYRY COPPER
EPIDOTE, CARBONATES, ZEOLITES
DICKITE, KAOLINITE, ILLITE, SMECTITE, MUSCOVITE
ALUNITE, JAROSITE, GYPSUM, ANHYDRITE
CHLORITE, BIOTITE, PHLOGOPITE, TOURMALINE
PYROPHYLLITE, DIASPORE, ZUNYITE, TOPAZ
SELECTED COPPER BEARING

15. ARGILLIC  ADVANCED ARGILLIC
PROPYLITIC
CHLORITE, EPIDOTE, ZEOLITES
MONTMORILLONITE, ILLITE, CARBONATE
POTASSIC
FELDSPARS, BIOTITE, PHLOGOPITE, CHLORITE, TOURMALINE
PHYLLIC
MUSCOVITE ILLITE, KAOLINITE, QUARTZ
ARGILLIC  ADVANCED ARGILLIC
TOPAZ, ZUNYITE, PYROPHYLLITE, DICKITE,
DIASPORE, KAOLINITE, ILLITE, ALUNITE
LEACHED CAP ENVIRONMENT
ALUNITE, KAOLINTE, ILLITE, DIASPORE, IRON OXIDES
CAPPER SULFATES, HYDROXIDES. HALLOYSITE

16. PROPYLITIC ALTERATION
Forms the outermost alteration zone at intermedite to deep levels in the porphyry system.
It can be mineralogically zoned from inner actinolite-rich to outer epidote rich facies. chlorite, epidote, albite, calcite, actinolite, illite, clay pyrite

17. PORPHYRY COPPER - PROPYLITIC ZONE MINERALS
DOMINANT ACCESSORY SECODARY ALTERATION
ALBITE ACTINOLITE* CHLORITE*
CALCITE* BIOTITE*(SECONDARY) HYDROUS BIOTITE
CHLORITE HEMATITE SERICITE
EPIDOTE ZEOLITES* SMECTITE*
QUARTZ* VERMICULITE*
*INFRARED ACTIVE MINERALS

18. PROPYLITIC ALTERATION
includes;
Fe- chlorite,
Mg-chlorite,
epidote,
actinolite,
calcite,
illite,
montmorillonite,
albite,
pyrite.
PROPYLITIC
PROPYLITIC

19. BIOTITE RICH ALTERATION (Thompson and Thompson, 1996)
POTASSIC ZONE
BIOTITE RICH ALTERATION
(Thompson and Thompson, 1996)
This alteration type is found in the core of porphyry deposits.
It may form large peripheral alteration zone in wall rocks (without K-spar) and zones out to propylitic alteration.
Minerals include biotite, phlogopite, K-spar, magnetite, quartz, anhydrite, albite-sodic plagioclase, actinolite, rutile, apatite, “sericite”, chlorite, and epidote.

20. POTASSIC
POTASSIC
- Potassic alteration shows Actinolite, biotite, phlogopite, epidote, iron-chlorite, Mg-chlorite, muscovite, quartz, anhydrite, magnetite.
Potassic - K-silicate alteration includes "albite", anhydrite, quartz, muscovite and epidote.

21. SODIC, SODIC-CALCIC
Occurs with minor mineralization in the deeper parts of some porphyry systems.
and is a host to mineralization in porphyry deposits associated with alkaline intrusions.
albite, actinolite, diopside, quartz, magnetite, titanite, chlorite, epidote , scapolite

22. SODIC – CALCIC ALTERATION
Albite,
actinolite,
Fe-chlorite,
epidote,
Mg-chlorite,
marialite, mizzonite,
diopside,
quartz,
magnetite

23. PHYLLIC ALTERATION
Phyllic alteration commonly forms a peripheral halo around the core of porphyry deposits.
It may overprint earlier potassic alteration and may host substantial mineralization.
Detectable minerals include
muscovite, illite, quartz, pyrite, chlorite, hematite, and anhydrite.

24. PORPHYRY COPPER - PHYLLIC ZONE MINERALS
DOMINANT ACCESSORY SECODARY ALTERATION
QUARTZ CHALCOPYRITE
PYRITE MOLYBDENITE KAOLINITE*
“SERICITE”/ILLITE* TOURMALINE*
“SERICITE”/MUSCOVITE*
*INFRARED ACTIVE MINERALS

25. Phyllic alteration includes: Illite, muscovite,
iron chlorite, Mg-chlorite,
gypsum, anhydrite,
quartz, pyrite.

26. STOCKWORKS
TOMBSTONE, AZ

27. PHYLLIC
TOURMALINE

28. TOURMALINE MINERALS ALTERATION DEPOSIT TYPE
Tour, Sericite PHYLLIC INTRUSION – PC Found in Phyllic zone
Pyrophyllite, Qtz AA INTRUSION-PC upper parts of PC
Sericite, Andal, Dia pyrite vein envelopes
Alun, topaz, Tour, dumo
Pyrite, Hem
Tour, Pyr, Chalco MINERALIZED PC as cement in mineralized BXA
Topaz, Muscovite, Greisen INTRUSION high Temp Alt – peraluminous Qtz, tourmaline granites –related mineralztn
Tour, Muscovite, Qtz TOURMALINE SMS pervasive replacement below
massive sulfide; Assoc w/
abundant dissem sulfides
limited to feldspathic strata.

29. INTERMEDIATE ARGILLIC
Intermediate argillic alteration generally forms a structurally controlled to widespread overprint on other types of alteration in many porphyry systems.
The detectable minerals include illite, muscovite, dickite, kaolinite, Fe-chlorite, Mg-chlorite, epidote, montmorillonite, calcite, and pyrite.

30. PORPHYRY COPPER - INTERMEDIATE ARGILLIC MINERALS
DONINANT ACCESSORY
CHLORITE* CHALCOPYRITE
ILLITE* GOLD
ILLITE/SMECTITE* HEMATITE
KAOLINITE* MAGNETITE
QUARTZ* PYRITE
SMECTITE*
*INFRARED ACTIVE MINERALS

31. INTERMEDIATE ARGILLIC
alteration
contains
muscovite,
illite,
chlorite,
kaolinite,
dickite, montmorillonite,
calcite,
epidote,
pyrite.

32. 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.

33. PORPHYRY COPPER - ADVANCED ARGILLIC MINERALS
DONINANT ACCESSORY
ALUNITE* CHALCEDONIC QUARTZ*
DICKITE* DISPORE*
KAOLINITE* GOETHITE
PYROPHYLLITE* JAROSITE*
QUARTZ*
*INFRARED ACTIVE MINERALS

34. ADVANCED ARGILLIC
higher temperature minerals
Topaz,
pyrophyllite,
andalusite,
dumortierite,
tourmaline,
alunite,
diaspore,
quartz,
hematite
pyrite.

35. SUPERGENE
Secondary (supergene) zones carry chalcocite, covellite and other Cu2S minerals (digenite, djurleite, etc.), chrysocolla, native copper and copper oxide, carbonate and sulphate minerals. Oxidized and leached zones at surface are marked by ferruginous “cappings” with supergene clay minerals, limonite (goethite, hematite and jarosite) and residual quartz.. Panteleyev, A. (1995):
Minerals include: antlerite, bisbeeite, brochantite, chalcoalumite, claringbullite, conichalcite, crednerite, cuprite, delafossite, graemite, nantokite, paramelaconite, paratacamite, rosasite and spangolite, aurichalcite, connellite, cyanotrichite, malachite and shattuckite are additional supergene copper.

36. COPPER CARBONATES
porphyry systems can include
Azurite
Malachite
Aurichalcite
Rosasite

37. CU phosphates include libelhenite, pseudomalachite, and turquoise.
Cu chlorides include
atacamite, connellite, and cumengite

38. Cu-ARSENATES
bayldonite,
chenevixite
conichalcite,
clinoclase
olivenite.

39. Cu-SILICATES
chrysocolla,
dioptase,
Papagoite
shattuckite

40. Cu-SULFATES antlerite, brochantite, chalcanthite, cyanotrichite,
kroehnite,
spangolite

41. LEACHED CAP
Minerals in the leached cap environment include alunite, kaolinite, illite, diaspore, iron oxides, copper sulfates, and copper hydroxides. AND HALLOYSITE

42. LEACH CAP MINERALS
goethite,
hematite,
jarosite,
kaolinite,
chrysocolla,
antlerite,
brochantite,
diaspore,
turquoise.
alunite.

43. Other leach cap copper bearing atacamite, azurite, malachite,
chrysocolla,
kaolinite.

44. Exotic copper mineralization
is a complex hydrochemical process linking supergene enrichment, lateral copper transport, and precipitation of copper oxide minerals in the drainage network of a porphyry copper deposit.

49. POTASSIC
ZONE
ALTERATION
MINERALS

50. MORE
POTASSIC
ZONE

51. PORPHYRY COPPER
ALTERATION
MINERALS

53. COPPER
BEARING
ALTERATION
MINERALS