ron wrote:
GoldnBoy wrote: nice sample, wonder what kind of grade that runs, must be over 1%????
wonder what kind of grades RonS is talking about for zonte to be a major discovery,is he thinking 300m at 1.50% of copper,and btw,the project has to be also an economical one,we mustn't forget that.
Good point, but 300m at 0.4% copper may be very good. You also have to consider the percent of iron, some have higher iron and less copper and vice versa. The amount of gold and silver content will also be a factor. Some also have rare earths too. Plus the other economic factors, strip ratio, location etc.
Lot of info here from a group of Australian/Europe experts for an evening of reading.
It appears ZON has a copper rich system with silver and gold from what we know so far.
www.unige.ch/sciences/terre/research/Gro...coppergold_seg05.pdf
Metal Contents and Sizes of IOCG Systems
The largest apatite-bearing Fe ore and IOCG systems contain
more than 1 billion tons (Gt) of Fe ore or Cu-Au ore and
commonly have significant quantities of accessory elements
including P, REE, Co, Ag and U (Table A1, Fig. 3, App. Fig.
A1). Relatively few deposits have a full suite of chemical data;
Fe deposits generally have reported Fe, P, S, and Ti, rarely
Cu, and in almost no cases Au or other trace elements. Conversely,
in Cu deposits, only Cu and Au are widely reported,
other trace element compositions are sparse, and data on Fe
contents are rare. Mineralogy and rock descriptions consequently
provide the main basis for recognizing similarities
among these deposits, although there are sufficient Cu data
from Fe deposits to suggest these could all represent a continuum
(Fig. 3).
Iron ore deposits average between 30 and 70 wt percent
Fe, corresponding to 50 to nearly 100 wt percent hematite or
magnetite (Fig. A1). In the few Cu-rich deposits for which Fe
data are available, concentrations range from 15 to 25 wt percent
Fe in the Cu ores. The difference in values reflects the
metals of interest, e.g., in the Candelaria Cu(-Au) deposit
large volumes of rock contain >30 percent Fe but do not coincide
with the Cu orebodies. The amount of magnetite contained
in the Candelaria system (i.e., not restricted to Cu-Au
ore) likely exceeds the amount in the largest Fe deposits of
the Chilean Fe belt, and the contained Fe in the Cu ore at
Olympic Dam approaches that of the largest Fe systems
known. Among the other ferrous metals, available data indicate
that Ti is scarce (<1 wt % TiO2; Fe/Ti > crustal Fe/Ti) in
both Cu and Fe ore types; Co and V can be enriched relative
to Fe, but Ni, Mn, and Cr generally are depleted relative to
Fe (Kisvarsanyi and Proctor, 1967; Frietsch, 1970; Hauck,
1990).
Copper grades from >60 Cu-Au deposits mostly fall between
0.5 and 4 wt percent, averaging about 1 wt percent;
they may form an approximate continuum with Cu contents
in Fe-dominant deposits, where reported concentrations are
not uncommonly on the order of 0.1 wt percent (Fig. 3). Most
Fe deposits lack Cu assays, even though chalcopyrite is com
monly described as an accessory mineral. Typically, Cu and
Au contents represent hypogene grades, although weathering
can remove Cu, leaving residual Au-only resources, as in the
upper part of the Igarape Bahia-Alemão system in the Carajás
district.