As the second most common mineral in the Earth’s
crust after feldspar, quartz has many well-known uses, from
window glass, to sandpaper, to cement.
Chemically, quartz is commonly understood as silica, or
silicon dioxide (SiO2), but it rarely exists in this pure form.
In nature, quartz contains various impurities, the type and
amount of which dictate the quartz’s
The most common kind of quartz, which occurs in rock or sand
form, is generally between 50% and 98% pure silica. Quartz
with a purity of over 99.995% silica (<50ppm of
impurities), is known as high purity quartz (HPQ) and is
extremely rare in nature.
It is this highly pure form of silica that has made
technologies such as solar photovoltaic (PV) panels and
There are only two consistent producers of commercial
quantities of ultra-HPQ, both of which are based in the US.
Unimin Corp. a subsidiary of Belgian industrial materials
group, Sibelco, is headquartered in Connecticut and The Quartz
Corp, a joint venture between Norwegian Crystallites and French
industrial minerals company, Imerys, is based in Spruce Pine,
Both Unimin and The Quartz Corp mine from the same deposit
in Spruce Pine, a small town which calls itself "Mineral City"
and is widely referred to as "silica valley".
In Russia, Russian Quartz LLC also claims to be a
substantial supplier of HPQ. In 2013, Japanese conglomerate
Sumitomo Corp. purchased a 28.69% equity stake in Russian
Quartz for $50m.
|HPQ largest growing
market is in solar photovoltaic
The uses of quartz
Rock quartz is mined and processed into crushed quartz,
which is then either used to produce silicon metal, or further
processed into quartz powder and quartz sand. The metal is
purified into polysilicon metal, which along with sand is used
to create semiconductors and solar crucibles.
Polysilicon is melted in a square crucible before being
cooled into ingots that make up multicrystalline ingots.
Monocrystalline silicon is produced using the Czochralski
Process (CZ), where a small piece of silicon metal is dipped
into molten polysilicon contained in a crucible and withdrawn
slowly while rotating. The silicon ingots are then cut into
The cut wafers then undergo final preparation to make PV
solar cells, usually in a fully automated production line in a
clean room environment. Wires are placed on the cell by screen
printing a silver paste onto the wafer and then firing it in a
Different etchings and textures, polishing and coatings are
applied to improve the optical and electrical characteristics
of the cell. One of the anti-reflective coatings is a silicon
nitride deposition, which gives the PV cells a blue colour.
Silicon wafers for semiconductors are also made using the CZ
process and are then physically and chemically polished to
remove microscopic marks, leaving a surface roughness of less
than one millionth of a millimetre. The wafer is then ready for
etching with a circuit design.
|The Quartz Corp’s Spruce Pine Mine.
The Quartz Corp.
|Substitutional and interstitial impurities are
as extrinsic point defects, as opposed to intrinsic
While the Spruce Pine deposits in North Carolina provide up
to 90% of the world’s solar and
semiconductor-grade HPQ, due to the confidential nature of
the industry, little is known about the area’s
Reiner Haus, managing director at Germany-based Dorfner
Anzaplan, has suggested that, excluding China, the size of the
international HPQ sand market now stands at 50-100,000 tpa. In
October last year, Russia based Kyshtym Mining estimated that
the entire global market stood at 65,000 tpa and that it was
growing at a rate of 3-5% per year.
Speaking to IM, The Quartz Corp said it currently has
permits to produce 30,000 tpa of HPQ from its plant in Norway,
using Spruce Pine and Norwegian quartz.
IM estimates that production from The Quartz
Corp’s two processing plants at Spruce Pine is
about 40,000 tpa.
There is no production of solar and semiconductor-grade HPQ
sand outside the big three producers of Unimin, Quartz Corp
(both from Spruce Pine) and Kyshtym Mining (or Russian Quartz).
Kyshtym claims to produce around 10,000 tpa from its deposit in
the Urals, Russia.
While little is known about China’s HPQ supply,
market sources indicate that the country does not have quartz
deposits of the right quality to produce high-end solar and
semiconductor-grade HPQ sand reliably and economically. It
therefore imports 100% of its requirements from one of the
three international producers.
Jiangsu Pacific Quartz Co. Ltd., located in Donghai, China,
claims to produce large quantities of HPQ products suitable for
the solar, semiconductor and lighting sectors, all of it
manufactured using predominantly imported Unimin HPQ
According to The Quartz Corp, Donghai is the centre of
China’s glass tube manufacturing industry, with
90-95% of the country’s output originating there.
It estimates that the production hub requires around 36,500 tpa
quartz, including an unspecified amount of HPQ for use in high
end applications as well as in high-intensity discharge (HID)
The murkiness of the quartz industry has not put off
would-be new suppliers, however, with some assuming that behind
the secrecy lie significant opportunities.
Chris Karamountzos, CEO of Australia-based Creswick Quartz
Ltd states that "while there may be debate as to the size of
the market, what is clear is that HPQ is a scarce and strategic
mineral that is in ever increasing demand."
"Customers have encouraged our entry into the HPQ market with
the carrot of reasonable volume [orders] and pricing," he
added. "They tell us that there is a growing disconnect
between the capabilities of established suppliers and the
pace of growth in the semiconductor and renewable energy
Ascertaining market prices for HPQ is a difficult task. Part
of the problem is the definition of HPQ differs depending on
end use specifications. HPQ sand for solar PV-grade CZ crucible
manufacture contains less than 30ppm impurities and
semiconductor-grade material requires a maximum of 10ppm
impurities. Elemental impurities also need to be within certain
IM’s sources indicate that while many common
forms of quartz sell for anywhere in the $25-250/tonne range,
fully beneficiated HPQ (<30ppm impurities) sells for
$6,000-25,000/tonne, depending on the application and
economic conditions. Solar-grade quartz currently fetches
Sources familiar with the semiconductor market in China have
suggested to IM that prices for semiconductor grade quartz can
range anywhere from $6,000/tonne to $12,000 /tonne, depending
on the contract, buyer, specifications and circumstances.
|Alaskite, on the right, is the Spruce Pine
mined by Unimin to supply 90% of the world’s
market. On the left is a seemingly purer type of
from Sugarbag Hill, which HPQ Materials hopes will
have a processing cost advantage.
The nature and type of impurities in quartz are critical to
the success of processing. They also complicate prospecting for
HPQ resources, since visibly clear and seemingly pure quartz
can turn out to be useless for high purity
Natural quartz always has defects. The defects most often
scrutinised in HPQ production are structural or substitutional
impurities and interstitial impurities. Substitutional
impurities occur where a silicon atom has been replaced in the
silica molecule itself, whereas interstitial impurities exist
between silica molecules and are generally easier to remove.
While impurities present the single largest problem for HPQ
end-users, novel processing methods are continually being
explored to remove them more effectively.
Spruce Pine quartz is naturally extremely low in lattice
bound elements, due to the nature of the quartz’s
formation. The Quartz Corp is able to purify Spruce Pine quartz
to extremely high levels (<20ppm impurities, or 99.998%
SiO2) at their purification plant in Drag, Norway.
| Note: Maximum chemical content
values used for each product
Source rock requirements
The factory at Drag has a number of proprietary processes to
produce high purity quartz. The first cleaning step is hand
sorting. The quartz then undergoes 10-12 mechanised treatment
processes, including both wet and dry cleaning.
The purity and grades of quartz vary between deposits, with
a range of grades found in different parts of the world (see
Jason May, chief technology officer at Australia-based High
Purity Quartz Pty Ltd (HPQ Materials), notes that good
processing goes a long way towards compensating for imperfect
source material. "Interestingly the US source rock –
Spruce Pine Alaskite – is the most impure [of the
grades shown in Table 1], but can be processed to the highest
purities through multiple and floatation processes". May points
out that such intensive processing is costly, and that starting
with a purer quartz rock can yield significant cost
HPQ Materials is developing the Sugarbag Hill quartz project
in northern Queensland, Australia. The company believes that
the natural purity of Sugarbag quartz provides an opportunity
for it to enter the HPQ market on a competitive footing.
"Although right now pricing is a secondary consideration to
supply security, it’s an added bonus that, once
our project is in production, it is likely to be the lowest
cost source globally of solar PV and semiconductor-grade HPQ
sand, in our estimations," Stuart Jones, HPQ
Materials’ CEO, told IM.
End product specifications for HPQ are strict, with at least
99.995% purity required by most entry level, lower grade quartz
applications. A silica content of at least 99.997% (<30ppm
impurities) is required for high-end applications like CZ
crucibles and quartzware machine parts for the solar industry,
while the semiconductor industry requires purity of 99.999%
(<10ppm impurities). Solar grade HPQ must contain less than
30ppm impurities after processing. If quartz cannot be
economically processed to these levels, it cannot be used for
high value applications and is only suitable for entry level
uses, such as halogen lighting and liquid crystal display (LCD)
In addition to low impurity levels, semiconductor-grade HPQ
must also be low in uranium and thorium content, something
that Lita Shon Roy, CEO of US-based electronic materials
consultancy Techcet, says is often overlooked. Even the small
amount of alpha radiation emitted by these elements in minute
concentrations is enough to cause errors in memory
Dorfner Anzaplan’s Haus suggests that uranium
and thorium should be less than 2 parts per billion (ppb) in
concentration and below 0.5 ppb in low alpha applications.
Additionally, the chemical make-up of impurities is
important and must adhere to strict ppm restrictions on
aluminium (Al), iron (Fe), lithium (Li), sodium (Na) and
The size of a quartz deposit and its capacity to produce
reliably are also considered by HPQ consumers when choosing a
supplier. Chinese, Indian, Madagascan and Brazilian quartz
suppliers often struggle to produce consistent volumes and
purities of quartz. One reason for their unreliable nature is
that these suppliers usually produce quartz from a number of
small deposits at a rate of no more than 2,000 tpa.
To achieve a consistent quality end product, a large volume
operation is usually needed to justify the up-front costs,
which need to amortise over a relatively long mine life. Quartz
from different sources cannot be blended, so using a
combination of resources with different chemical signatures
requiring different processing tends to be prohibitively
|Blasting at Spruce Pine.
The Quartz Corp
Opportunities and hurdles
Both raw and processed HPQ already command high prices and
according to industry sources, the material’s
value is increasing as suppliers struggle to keep up with
rising demand from high-tech and green energy
Techcet’s Shon-Roy told IM that the
semiconductor industry is risk averse and often not willing to
change suppliers, due to the need to meet stringent
Few quartz mines globally come up to scratch when it comes
to producing semiconductor-grade HPQ – a fact which
partly explains why Unimin has been able to effectively corner
But the Spruce Pine deposits, which Unimin has been mining
for over 50 years, cannot last forever and it is unclear how
much longer these mines have left to run. "While Spruce Pine
may have remaining deposits, there is no transparency on how
much [they contain], or whether the residual quantities can
be processed at the same operating cost," points out HPQ
Materials’ May. If Spruce Pine’s
ore is declining in quality, May suggests that Unimin may
have to increase quartz prices to protect margins.
HPQ Materials’ Jones suggests that information
published by HPQ buyers offers a clearer picture of the supply
situation. US-based Momentive Performance Materials,
which according to US Securities and Exchange Commission (SEC)
filings is a large buyer of Unimin’s HPQ sand, has
repeatedly said in its annual 10K forms that Unimin "exercises
significant control over quartz sand prices". As a buyer,
Momentive said that it faces annual price increases of 3-5% for
In its 10K form for the financial year ended 31 December
2015, Momentive said that it procures quartz from other
suppliers in addition to Unimin, but warned that "should any of
our key suppliers fail to deliver these or other raw materials
or intermediate products to us, or no longer supply us, we may
be unable to purchase these materials in necessary quantities,
which could adversely affect our volumes, or may not be able to
purchase them at prices that would allow us to remain
The company further highlighted that, in the past, some of
its suppliers have experienced force majeure events, which
meant they could not fulfill deliveries of contracted-for raw
materials. "On these occasions, we were forced to purchase
replacement raw materials in the open market at significantly
higher costs or place our customers on an allocation of our
"In addition, we cannot predict whether new regulations or
restrictions may be imposed in the future," it added.
Jones argues that the risks of HPQ supply concentration are
increasingly relevant to the solar PV and semiconductor
industries, which invest billions of dollars to expand capacity
on the assumption of being able to secure the raw materials
The Quartz Corp however paints a different picture of the
supply situation. The company told IM that it has "enough
capacity to produce more than the demands of our customers and
our internal demand in Norway".
"Global production capacity for HPQ sand is more than twice
the foreseeable market demand," The Quartz Corp added, pointing
to recent plant expansions and modernisations by the main
|Quartz Corp.’s drag mineral separation
The solar industry has played a big part in HPQ demand in the
last decade and its role is set to grow as new large and
innovative solar investments are announced. US electric
vehicle maker, Tesla Motors Inc., this year announced its
intention to acquire Californian solar energy producer,
SolarCity Corp., for $2.6bn. Tesla said the buyout would
allow it to achieve lower hardware and marketing costs and
boost manufacturing efficiency, creating the
"world’s only vertically integrated sustainable
The cost of installing solar is also going down.
Anglo-Australian mining giant, BHP Billiton Ltd, recently
stated that, "on average, wind and solar energy are expected to
reach cost-parity with incumbent technologies on a new-build,
unsubsidised basis in about a decade".
In some areas, such as Mexico, solar is already at cost
parity with conventional energy generation. In a recent
online article, The Quartz Corp stated that lower solar PV
module prices will impact the cost of energy and potentially
lead to increased investment in solar installations, both
large and small.
The company added that lower prices of installation could
benefit suppliers of monocrystalline panels, which require
slightly higher purity quartz than poly- or multicrystalline
panels. "Countries where balance of system costs [all costs
except the PV panels] are higher, such as Japan and Australia,
are more likely to use high efficiency monocrystalline modules,
as fewer units are required to generate the same number of
kilowatt hours (kWh) [than for [polycrystalline technologies],"
the company said.
Speaking to IM, The Quartz Corp. said that the solar market
is shifting towards higher efficiency products, which is
broadly good news for HPQ demand. "However, manufacturing
improvements mean that the amount of quartz used per panel is
dramatically reducing," it added.
According to a report by Zack’s Equity Research
earlier this year, the biggest driver of semiconductor growth
today is the increased use of cloud computing, which relies on
dense, energy efficient data centres.
The Semiconductor Industry Association (SIA) however expects
semiconductor sales to decline 2.4% this year, following a
According to The Quartz Corp., the semiconductor market is
"cyclical". "Currently, the market is following global GDP
trends, and is likely to continue to do so in the future.
Growth in the Chinese semiconductor market will help drive
demand for new production facilities, creating new
opportunities for HPQ applications," the company told IM.
Addressing concerns over the potential replacement of silicon
by other materials in semiconductors, The Quartz Corp in a
recent blog post said that "silicon is forecast to remain the
main material used in semiconductors, due in no small part to
the cheaper cost and mature manufacturing technology."
"While new, smaller architectures may require non-Si
products, it is very unlikely that the market will replace
silicon use in the near to midterm future," it added.
|Poly/multicrystalline versus monocrystalline solar
panels. Both types of panel
serve the same function in the overall solar PV system.
Mono panels are
typically more expensive, but are more efficient than
Emerging quartz producers
Thanks to the lowering of costs in technologies such as
solar PV and renewed interest in high-tech and green energy
applications generally, budding HPQ producers may have an
easier time finding funding and customers for their
Due to their proximity to growing Asian markets, Australian
and New Zealand quartz deposits are particularly well placed
Creswick Quartz’s Karamountzos told IM that,
after years navigating the Chinese market, Creswick is now the
country’s only exporter of HPQ for semiconductor
The company’s quartz deposits in the Australian
state of Victoria contain underground resources totalling
"billions of tonnes", according to Crewick, as well around 3m
tonnes above ground from old mine tailings left over from
previous operations at the sites.
"Our quartz has been proven by an extensive investigation,
conducted both locally with Australia’s
Commonwealth Scientific and Industrial Research Organization
(CSIRO), with our customers and with prospective end-users,"
Karamountzos told IM.
"We have taken a markedly different approach to established
suppliers in that we send our quartz to our customers in China
for refining, thereby taking advantage of refining expertise
and of course lower production costs".
Creswick claims that, once processed, its quartz has a purity
equivalent to, or higher than, Unimin’s Iota-6
material. This makes it suitable for the most stringently
quality-controlled HPQ applications, including
"Our quartz has already entered the HPQ market,"
Karamountzos told IM. "We expect this will become the most
exciting part of our business for as long as the world has
Meanwhile, HPQ Materials, which is also based in Victoria,
is in the latter stages of investment, with plans to start
producing HPQ sand in 2017.
The company is already accepting pre-sales orders for its
high purity and solar-grade sand, with its first three years
of production already booked – setting it apart from
some of its Australian rivals, which have achieved low grade,
low-priced sales to Chinese producers, according to May.
HPQ Materials aims to become the first Australian company to
manufacture solar PV and semiconductor-grade HPQ sand within
Australia and is also exploring opportunities to manufacture CZ
crucibles for export.
With five tenements covering 771 square kilometres around Mt
Isa in Queensland, Australia, Nova Strategic Minerals also
hopes to begin supplying quartz to the Asia Pacific high
purity quartz market.
Nova’s Director Mark Struthers spoke with IM,
confirming that they are targeting strong growth prospects
particularly in the Asia Pacific, driven primarily by the
The tenements, which could contain around two million tonnes
of quartz, have been sampled and analysed. Raw samples, drill
core samples, as well as rock chip samples have returned a
"consistant" >99.95% SiO2 minimum result (<500ppm other
The company has also successfully upgraded some of its
99.98%SiO2 quartz to 99.99%SiO2 in an effort to understand
whether or not their quartz is suitable for processing. The
company added that both boron and phosphorous were below 1ppm
during the trials.
With encouraging results, as well as a potentially large
resource, the company hopes to find a suitably qualified
partner who can add strategic and financial value to the
ASX-listed Rum Jungle Resources Ltd likewise claims that its
Dingo Hole silica project in the Northern Territory could be a
potential contender in the HPQ supply market, although an
announcement to the ASX in October last year stated that
chemical analyses of selected chip samples were inconclusive in
determining whether Dingo Hole ore is suitable for HPQ
In New Zealand, silica deposits in the Hokonui Hills in
South Island’s Southland region have sparked
interest following research undertaken by the Norwegian
Foundation for Scientific and Industrial Research.
The results of the foundation’s investigations
in this area indicate that Southland silica may be suitable for
electronic and solar-grade applications. One company looking to
develop the resources is Nomad Mining Ltd, which is currently
at an early stage of exploration but aims to ultimately develop
a silica refinery and subsequent quartz export business in New
Silica and silicon
Silica should not be confused with silicon metal (Si), made
from lower grade silica ore.
Silicon metal is also used in the PV solar industry, as
polysilicon metal to make PV cells.
To make polysilicon metal (>99.99999% purity), silica is
first turned into 98-99.99% silicon metal by removing oxygen in
Unimin’s Iota quartz
Unimin’s Iota quartz is the industry benchmark
and product of choice for semiconductor production as it
exhibits properties that make it ideal for the manufacture of
fused quartz crucibles used in the CZ process.
Unimin’s purest grade, Iota-8, is 99.9992% SiO2,
containing only 80ppb of impurities
Editor's note: Please note that Table 2 & 3
in this article was updated on 4 January to include The Quartz
Corp's NC1-CG product (instead of Norwegian Crystallites
The %SIO2 figure for the USA in Table
1 was also corrected to 96.877%.