Bulletin of the Mineral Research and Exploration

The Dağbaşı skarns have developed as an exoskarn type along the nearest
border of Upper Cretaceous Dağbaşı Granitoid and block- and lens-shaped
limestones of Berdiga Formation. The early garnets are predominantly grossular
type (And0–0.81Grs59.69–78.65Prs21.35–38.11),
while pyroxenes have a composition between diopside and hedenbergite
(Hed24.44–31.81Diy67.3–76.99Joh0.52–0.88). The late garnets are characterized
by high andradite (And74.67–100Grs0–22.8Prs0–4.51), and late pyroxenes by
increasing johannsenite content (Hed22.17–62.63Diy0–36.2Joh31.86–76.69). High
andradite content of late garnets is similar to Cu–Fe-type skarns, whereas the
higher johannsenite and Mn/Fe ratios of pyroxenes are similar to Zn-type
skarns. Higher andraditic garnets indicate an oxidized-type skarn and
association with the shallow emplacement of intrusion. Increasing And/Grs
ratios of garnets, from core to rim, also point out to increasing degree of
oxidation. The retrograde skarn minerals are epidote, tremolite-actinolite,
quartz, calcite, and chlorite. The ore minerals are composed of magnetite,
hematite, pyrrhotite, pyrite, chalcopyrite, sphalerite, and galena. The Ag
content of the galena (1.18-1.43wt%) suggests significant silver potential.
Dağbaşı Granitoid shows high-K (2.38–3.75wt.% K2O), calc-alkaline, metaluminous–peraluminous transitional
(A/CNK=0.88–1.23) and volcanic arc type granitoid. The various main and trace
element contents of the granodiorite observed along the skarn zones show
similarities with Fe–Cu–Zn type skarn-related granitoids, whereas there is no
clear relation between the skarn type and composition of outher granitoids.
Therefore, the presence of sulfur phases in addition to the oxide ore suggests
that geochemical characteristics of granitoid had a large effect on the mineral
composition.