2379
Enhanced Understanding of Telluride Flotation to Improve Gold
and Tellurium Recovery
Kylie Blackwell, Bogale Tadesse, Laurence Dyer
Western Australian School of Mines, Curtin University
ABSTRACT: Tellurium is playing a growing role in the transition to renewable energy. Demand for this rare
element used in the production of thin film solar panels and thermoelectric devices is increasing. Tellurium is
predominantly a by-product of copper processing.
Gold deposits are a viable source of tellurium in the form of gold telluride minerals. Approximately 20% of the
gold in the Golden Mile orebody in Kalgoorlie is present as gold-silver tellurides. Despite nearly 100 years of
gold flotation, little is known about the flotation properties of gold and silver telluride minerals.
Calaverite (AuTe2) and hessite (Ag2Te) form the basis of this study. The natural floatability of calaverite and
hessite is examined via zeta potential and microflotation test work. The addition of xanthate (PAX) is found to
have a destabilising effect on flotation froth. The use of kerosene was found to enhance natural aggregation and
flotation of calaverite and hessite.
INTRODUCTION
Tellurium is playing a growing role in the transition to
renewable energy (McNulty &Jowitt, 2022). Demand for
this rare element used in the production of thin film solar
panels and thermoelectric devices is increasing (Calvo &
Valero, 2022 Valero et al., 2018). Most tellurium is pro-
duced as a byproduct of copper and lead processing, pri-
marily from anode slimes during the copper refining stage
(Mahmoudi et al., 2020 Makuei &Senanayake, 2018
Schlesinger et al., 2011).
Tellurium is most often found as tellurides of gold,
silver, nickel, copper, lead and mercury (Afifi et al., 1988
Hayes et al., 2013 Shackleton et al., 2003). In copper ores,
tellurium is present as telluride minerals however, only 4%
of the tellurium reports to the copper anodes with 90%
being rejected in the flotation stage (Josephson, 2016
Nassar et al., 2022).
Gold deposits are a viable source of tellurium in the
form of gold telluride minerals (Goldfarb et al., 2017
Green, 2009). The Golden Mile deposit in Western Australia
is the largest Archaean orogenic lode gold system in the
world (Bateman &Hagemann, 2004 Shackleton et al.,
2003). Approximately 20% of the gold in the Golden Mile
orebody is present as gold-silver tellurides with the most
prevalent being calaverite (AuTe2) and petzite (Ag3AuTe2)
(Shackleton et al., 2003). Currently gold is extracted but
not tellurium.
These scenarios present an opportunity to increase the
production of tellurium by improving the performance of
existing operations and to develop technologies that enable
the extraction of multiple commodities (Bleiwas, 2010
Green, 2009 Valero et al., 2018).
This study investigates the flotation performance of
calaverite (AuTe2) and hessite (Ag2Te). Understanding the
Enhanced Understanding of Telluride Flotation to Improve Gold
and Tellurium Recovery
Kylie Blackwell, Bogale Tadesse, Laurence Dyer
Western Australian School of Mines, Curtin University
ABSTRACT: Tellurium is playing a growing role in the transition to renewable energy. Demand for this rare
element used in the production of thin film solar panels and thermoelectric devices is increasing. Tellurium is
predominantly a by-product of copper processing.
Gold deposits are a viable source of tellurium in the form of gold telluride minerals. Approximately 20% of the
gold in the Golden Mile orebody in Kalgoorlie is present as gold-silver tellurides. Despite nearly 100 years of
gold flotation, little is known about the flotation properties of gold and silver telluride minerals.
Calaverite (AuTe2) and hessite (Ag2Te) form the basis of this study. The natural floatability of calaverite and
hessite is examined via zeta potential and microflotation test work. The addition of xanthate (PAX) is found to
have a destabilising effect on flotation froth. The use of kerosene was found to enhance natural aggregation and
flotation of calaverite and hessite.
INTRODUCTION
Tellurium is playing a growing role in the transition to
renewable energy (McNulty &Jowitt, 2022). Demand for
this rare element used in the production of thin film solar
panels and thermoelectric devices is increasing (Calvo &
Valero, 2022 Valero et al., 2018). Most tellurium is pro-
duced as a byproduct of copper and lead processing, pri-
marily from anode slimes during the copper refining stage
(Mahmoudi et al., 2020 Makuei &Senanayake, 2018
Schlesinger et al., 2011).
Tellurium is most often found as tellurides of gold,
silver, nickel, copper, lead and mercury (Afifi et al., 1988
Hayes et al., 2013 Shackleton et al., 2003). In copper ores,
tellurium is present as telluride minerals however, only 4%
of the tellurium reports to the copper anodes with 90%
being rejected in the flotation stage (Josephson, 2016
Nassar et al., 2022).
Gold deposits are a viable source of tellurium in the
form of gold telluride minerals (Goldfarb et al., 2017
Green, 2009). The Golden Mile deposit in Western Australia
is the largest Archaean orogenic lode gold system in the
world (Bateman &Hagemann, 2004 Shackleton et al.,
2003). Approximately 20% of the gold in the Golden Mile
orebody is present as gold-silver tellurides with the most
prevalent being calaverite (AuTe2) and petzite (Ag3AuTe2)
(Shackleton et al., 2003). Currently gold is extracted but
not tellurium.
These scenarios present an opportunity to increase the
production of tellurium by improving the performance of
existing operations and to develop technologies that enable
the extraction of multiple commodities (Bleiwas, 2010
Green, 2009 Valero et al., 2018).
This study investigates the flotation performance of
calaverite (AuTe2) and hessite (Ag2Te). Understanding the