The name 'kaolin’ is derived from the village
of Gaoling in Jiangxi province, China, where the white clay was
mined. The nearby Jingdezhen potteries used the kaolin to
create their fine white porcelain. Europeans identified the
composition of Chinese porcelain in the 18th Century and
deposits of kaolin were sought in Europe. This led to the
discovery of the kaolin deposits in Cornwall, southwest
England, which were named china clay.
Kaolin is white commercial clay consisting predominantly of
the mineral kaolinite, a hydrated aluminosilicate. Kaolinite,
Al2Si2O5 (OH)4 is triclinic, the other associated kaolin group
minerals (halloysite, nacrite and dickite) being monoclinic.
Kaolinite and halloysite are the most commonly found members of
the kaolin group whilst nacrite and dickite are considered
rare. However, with the progress made in infrared spectroscopy
techniques, nacrite and dickite are now being found in
association with kaolinite in many deposits.
The levels of nacrite and dickite are used as a guide by the
oil industry as an indication of depth of burial of sediments,
the levels of the two minerals increasing with higher
temperatures and pressures at depth.
Types of deposits
Kaolin deposits are encountered throughout the world and new
deposits are still being discovered. A deposit may be
classified as either primary or sedimentary. Primary, or
residual deposits, were formed by the alteration in situ of the
parent rocks, which may have been igneous, metamorphic or
volcanic in origin, by hydrothermal and weathering processes.
Sedimentary, or secondary, kaolin is derived from the erosion
of pre-existing rocks and the subsequent transport and
deposition of the clay.
In Cornwall and Devon, the kaolinite is derived from the
late-stage magmatic or hydrothermal decomposition of feldspar
within granite. It is separated from the host granite by
washing it out with high-pressure water hoses, a process known
as monitoring. The kaolin content rarely exceeds 20% of the
altered granite, but the depth of kaolinisation extends in many
places down to 300m. In Western Australia, vast tracts of
granitic rock have been weathered down to 50m, and the kaolin
content often exceeds 40%.
The best-known sedimentary kaolin deposits are from Georgia
in the US and the Amazon Basin in Brazil. The deposits of
kaolin were formed from the erosion of deeply weathered
crystalline rocks in plateau areas, which were then
transported and deposited as sedimentary sequences. Here, the
kaolin is found in lenses, often between 5-20m thick, and
with a high percentage of kaolinite, around 80-95%, which is
Global production of kaolin
Kaolin is found in many countries but it is just the
beneficiated, or refined clays that will be considered in
this article. Worldwide production is estimated by the US
Geological Society (USGS) to be 34m tonnes per annum (tpa).
However, this value includes 4.5m tpa (largely
unprocessed) from India and 3.1m tpa (tonnage of matrix mined
not processed) from Czech Republic, which distort the figures
for production. Global sales of processed kaolin in
2015 were estimated by USGS to range from 25-27m tonnes.
Since 1980 there has been a lot of consolidation within the
Whilst the situation with the major players has not changed
much, some significant producers have been acquired by the
Imerys acquired Goonvean Ltd in Cornwall in 2013, which had
a capacity of 180,000 tpa and several mines. AKW acquired
Bulgarian company Kaolin AD with estimated production of
An estimate of global production of kaolin in 2015 for
processed material is 25.23m tonnes with a regional split shown
in Figure 1. Six countries account for 66% of global production
in Figure 2.
|Figure 1: Regional share of global
of 25,23m tonnes for 2015
|Source: USGS, BGS, Ian Wilson
|Figure 2: Six countries account for 66%
|Source: USGS, BGS, Ian Wilson
|Table 1: Consolidation of kaolin companies
|Source: Ian Wilson
Imerys is the largest kaolin company in the world and
accounts for an estimated 20% of global production.
Imerys produces kaolin in Australia, Brazil, France,
New Zealand (Halloysite), Portugal, Thailand, Ukraine, UK
and the US.
The kaolin division manufactures a full range of products for
the paper and packaging paints, plastic or polymers, adhesive
and sealants, and ceramic industries. Imerys is the world
leader for kaolin used in paper.
Kaolin Reserves and Resources
In 2015 Imerys reported proven and probable reserves of
96.2m tonnes with 78% in the Americas (includes the US and
Brazil), 20% in Europe (includes Cornwall, UK) and Asia/Pacific
(2%) as shown in Table 2. For comparison figures for
2014 are shown and note that these included a breakdown for
North and South America as in 2015 it reports a combined
In 2014 the split of proven and probable reserves was 40%
for South America (predominantly the Amazon deposit in Brazil),
38% in North America, 20% in Europe and 2% in Asia/Pacific.
Kaolin total resources (measured, indicated and inferred)
for 2015 was 170.7m tonnes split between Americas (89%), Europe
(7%) and Asia/Pacific (4%).
US production in 2015 was down by 2% (5,000 tonnes) from
2014 and exports down by 222,000 tonnes. For 2015 imports
of kaolin were 88% from Brazil. 2.45m tonnes of kaolin
was exported to Japan (17%), Mexico (5%), China (14%), Finland
(9%) and Canada (8%).
Of the 6.16m tonnes production, 90% (5.54m tonnes) is from
Georgia with 5% from South Carolina and 5% from Alabama,
Arkansas, Texas, Florida, North Carolina and California.
The main producers in Georgia are KaMin LLC (formerly
Huber), Thiele, Imerys (formerly English China Clays) and BASF
(formerly Engelhard) who formed the China Clays Producers
About 40% of all kaolin sold was water-washed, followed by
calcined clay (20%), airfloat (20%), delaminated (15%) and
unprocessed (5%) as shown in Figure 3.
|Table 2: IMERYS: Kaolin Reserves Estimates
for 2014 and 2015 ('000 tonne)
|Source: Imerys-2016 Registration
|Figure 3: US production by process for 2015
Changes in Georgia
Imerys acquired BASF’S PHK (paper hydrous
kaolin) in November 2015 while BASF retains its important
calcined clay operations. The acquisition does not
involve any production assets but will take on
BASF’s patents, brands, customer relationships and
contracts, but not the company’s existing staff.
The transaction also includes the Gibraltar mill in
BASF will continue to own and operate its assets in Georgia,
including kaolin reserves, mining and production facilities as
well as a slurry facility in Ghent, Belgium. The changes are
due to several key markets declining including graphical paper,
ceramics and proppants. The market for graphical paper
continues to decline as e-media becomes more popular.
KaMin – shortly after the Imerys acquisition of
BASF’s PHK business, KaMin acquired the ultrafine
paper hydrous kaolin (UPHK) business. The UPHK business
was part of the recently acquired paper hydrous kaolin (PHK)
business from BASF. Imerys will retain all of the
non-UPHK business from the BASF transaction. The
transaction for acquiring UPHK did not involve any production
assets. KaMin will have a large share of the ultrafine
clay market with its operation in Brazil (CADAM) and the plant
at Wrens, Georgia.
KaMin said that Imerys had reviewed all the available
strategic options for the UPHK operations and concluded that
the deal offered the "best option for a smooth and efficient
transition of the existing UPHK customers". Imerys said that
KaMin could provide a "sustainable long-term source supply of
ultrafine kaolin for these customers".
KaMin has the know-how and unique process to produce the
very fine clays and sufficient capacity in their Georgia
facilities. The fine particle clays are the most widely used
worldwide in numerous coating applications. Delivering
the highest gloss and coatings solids, the fine particle clays
are the perfect complement in high carbonate coating
formulations to optimise properties and printability. Ultrafine
clays produced from CADAM (Brazil) are Amazon Plus and Amazon
Premium and from Wrens (Georgia) Hydrafine 90, Hydrafine 90W,
Hydragloss 90 and Hydragloss 91.
KaMin fine particle technology has also delivered
performance benefits in diverse industrial applications such as
paint, plastics, rubber, adhesives, and inks.
On 1 April 2008 IMin Partners acquired the kaolin business of
Huber Engineered Material and named the company KaMin LLC.
Tom Chambers, partner and co-founder of IMin Partners
based in in Fort Worth, Texas, is a private equity capital
fund dedicated to investing in specialty minerals and
Production of kaolin in China was estimated at 4m tonnes in
2015, with its major market being ceramics.
Kaolin deposits are found in a wide range of geological
settings both in the coastal and the inland provinces of
southern China. The largest primary resources have been derived
from the alteration of granitic rocks and their extrusive
equivalents. High-quality kaolin at Longyan in Fujian province
is suitable for high-quality tableware.
China is the largest producer of ceramics in the world and
relies on local kaolin resources with some imports of higher
The sedimentary kaolin in Maoming, with production of
250,000 tpa is the only significant producer of coating clay in
China with reasonable brightness and viscosity for coated
However, finer particle size distribution, good rheology
kaolin is imported mainly from Brazil and the US. Most of the
paper filler now utilises group calcium carbonate (GCC) and
precipitated calcium carbonate (PCC) with abundant marble and
limestone sources in China.
Whilst the paper market has increased, the level of coating
clay has decreased over the last decade with up to just 10%
used in the top coat mixed with GCC at 95% <2µ and
Also well known in China are the so-called hard kaolins that
are greyish clays, often with low iron and titania,
associated with coal measures in northern China. On
calcination, these grey clays produce a high-quality, high
brightness calcined product suitable for paper and speciality
Imports of Kaolin
Imports of kaolin from the US, Brazil and others are shown
in Table 4 and plotted in Figure 4. The US accounts for
88% of the imports with Brazil (12%) and others (9%).
|Figure 4: Imports of kaolin into China from
USA, Brazil and
others from 2011-2015
|Table 3: US: Production, imports,
exports and apparent consumption (2015)
(1) Defined as production (sold or used) +
imports - exports
Source: Daniel Flanagan, USGS Mineral
Commodities, January 2016
Exports of Kaolin
Chinese customs report that 1.1m tonnes with a value of
$108m was exported in 2015 with 93% to ten countries in Asia
China is the largest global paper producer in 2015 with
107.1m tonnes, an increase of 2.29% from 2014.
Consumption in 2015 was 103.5m tonnes, an increase of 2.79%
from 2014. A split of the grades for 2015 is shown
in Figure 7.
In 2015, compared to 2014, there was a decrease of newsprint
(-9.23%) and coated paper (-0.65%), with increases in printing
and writing paper (1.75%), tissue (6.63%), packaging paper
(2.31%), coated board (2.31%), liner/kraft (2.98%), corrugating
grade (3.25%), specialty paper (6.0%) and other paper and board
|Figure 5: Imports of kaolin into China from
Brazil and others (%), 2015
|Source: Chinese Customs
|Figure 6: Exports of kaolin from China (%) in
|Source: Chinese Customs
|Figure 7: Chinese production of paper and
of 107.1m tonnes in 2015 (%)
Source: Chinese Paper Association, June 2016
Production of beneficiated kaolin in 2015 is estimated at
301,050 tonnes with 191,000 tonnes (63%) for hydrous kaolin and
110,050 tonnes (37%) calcined clay.
Production and capacity of processed hydrous kaolin is shown
in Table 5 and calcined clay in Table 6.
45,000 tonnes of fine particle size hydrous kaolin was
imported in 2015 from the US by KaMin and Thiele (Kaofine 90)
for paper coating. 8,000 tonnes of calcined clay were imported
in 2015 by Imerys (grades Neogen and Polestar 501) and by CMP
Shanxi (CMP 90).
According to Chinese customs 29,814 tonnes of kaolin were
exported to India at a value of $6.1m.
|Table 4. China Imports of kaolin from USA and
Brazil and average prices 2011-2015
|Source: Chinese Customs
|Table 5: Production of hydrous kaolin in
|Source: Pramod Pillai, former GM at EICL and
|Table 6: Production of calcined clay in India
|Source: Pramod Pillai, former GM at EICL and
|Table 7: SAWA Clay sand and clay products and
English Indian Clay Ltd (EICL)
EICL Limited (formerly known as English Indian Clays
Limited), a company incorporated in India in 1963, under the
Companies Act 1956, was part of the Thapar Group. The company
is engaged in the business of mining of clay (kaolin) and the
manufacturing of processed clay and starch.
The history of the Indian kaolin industry is directly linked
to EICL since it was the first processed kaolin plant to be put
up in 1963 by the Maharaja of Travancore and a local
businessman. English China Clays Ltd became involved in
technical and financial collaboration.
In 1992 ECC had a policy not to be involved in joint
ventures and at the time production was around 20,000 tpa.
Since 1992 EICL increased the production of
hydrous clay significantly and introduced calcined clay.
At present EICL is the leading producer of hydrous kaolin and
calcined clay, as shown in Tables 5 and 8.
EICL entered into a joint-venture agreement with MAC Group
Limited of Tanzania in FY 2014-15 for prospecting of mines
and evaluation of a proposed clay manufacturing facility in
Tanzania (East Africa) based on the Pugu kaolin deposit.
In the EICL Notes to Account, Year End March 2016, it
was reported that there was no further progress during the
Ashapura used to use kaolin from the Bhuj mine that was
mainly used in their crude washing plants for ceramic and white
cement in break-bulk shipments. After a failed attempt
to set up a hydrous clay plant in Trivandrum, Kerala, Ashapura
no longer produces any hydrous clay anywhere now. However
the Kerala plant has been relocated to Bhuj and has been
updated, which has led to some optimism that the company could
yet become an important producer, albeit with kaolin sources
The plant commissioning of 50,000 tpa hydrous kaolin and
25,000 tpa calcined clay (30,000 tpa hydrous kaolin feed) is
expected to be online in November 2016.
Progressive & Popular Minerals Pvt. Ltd
MS Sawa Clay & Minerals Pvt. Ltd. (MSSCMPL) is an
associated company of Progressive & Popular Minerals Pvt.
Ltd. Its mines hold proved mineable mineral reserves of more
than 250m tonnes and are located in close proximity to a sand
washing plant in Sawa, District Chittorgarh, Rajasthan in the
northwest of India. The processing plant is 2.5km from
the mine with the nearest railway loading yard 8km away at
Station Shambhupura. The nearest port Kandla/Mundra is 650 km
MS Sawa Clays mine a white kaolinitic sand with a view of one
of the opencast pits in Figure 8.
The process produces three types of sand and three types of
clay based on the particle size.
The products, dry weight TPD (tonnes per day) and
For clay the process entails a hydrocyclone systems,
screening and for finer grades passes through a centrifuge
with bleaching and further screening. This is then
filter pressed, flash dried then milled in a Raymond mill and
subsequently auto-packed into 25 and 50kg bags.
Tellus Holdings Ltd
Tellus is developing the Sandy Ridge facility 140km
northwest of Kalgoorlie, Western Australia primarily for waste
disposal in voids created by the mining and for processing of
the removed kaolin.
Sandy Ridge kaolin deposit is approximately 160km long, 20km
wide, flat, overburden 6m deep, kaolin thickness 7 to 24m thick
with an average of 14m. The kaolinised granite has an inferred
resource of 41.3m tonnes. Stage 1 of production
will be 12,000 tpa with the plant built with a capacity of
40,000 tpa. Stage 2 will be dependent on market demand.
Kaolin will be in one tonne big bags loaded into containers
at the plant, taken by rail to Freemantle Port and to Asia by
container ship. The kaolin sales will be aimed for export for
Asian market for tableware ceramics as well as being suitable
for glass fibre, ceramics, paint and others.
The voids resulting from mining will be used to
provide Western Australia with a licensed facility that
safely allows for the storage, treatment, recovery and
permanent isolation of bulk waste products, or the secure
storage and isolation of hazardous materials.
Some of these products may be classified as dangerous or
hazardous goods, such as those listed wastes under Schedule 1
of the National Environment Protection (Movement of Controlled
Waste between States and Territories) measure or NEPM
Waste not accepted is Nuclear Waste as defined in the nuclear
waste Storage and Transportation (Prohibition) Act 1999,
Intermediate level (ILW), High-level radioactive waste (HLW)
and Infectious or clinical materials (excluding
Altech Chemicals Ltd
Altech is aiming to become one of the world`s leading
suppliers of 99.99% high purity alumina (HPA). HPA (Al2O3) in
HPA is a high-value, high margin and highly demanded product
as it is the critical ingredient required for the production of
artificial sapphire. Artificial sapphire is used in the
manufacture of substrates for LED lights, semiconductor wafers
used in the electronics industry and scratch-resistant
artificial sapphire glass. Sapphire glass is used in models of
the Apple watch. There is no substitute for HPA in the
manufacture of artificial sapphire.
Altech was recently granted its mining lease at Meckering,
where it is planning to mine 120,000 tonnes of kaolin every
three years on a campaign basis with each one lasting two
months. The kaolin matrix will be stockpiled, placed
into standard shipping containers at the rate of 40,000 tpa and
transported to Johor, Malaysia for processing into HPA at the
company’s proposed plant. The Meckering
deposit covers approximately 1,000 km2 in area and has an
indicated and inferred Resource estimated at 65m tonnes with
Swan River Kaolin (SRK) carried out exploration and
development work at the deposit in the 1990’s.
Pilot trials were carried out at SRK’s
facility in Northam, WA on a 48-tonne bulk sample from a trial
pit with 19 tonnes produced that was suitable for paper and
On 27 April 2016 Altech signed an offtake sales arrangement
with Mitsubishi for the first 10 years of production and
secured sales for 100% of proposed 4,000 tpa HPA.
The take off sales for year 1 will be 2,700 tonnes building
up to 3,800 tonnes (year 4) and 4,000 tonnes (years 5-10).
|Figure 8: View of MS Sawa Clay mine
Western Australia Kaolin
In Western Australia, the kaolinised granite deposits were
evaluated in great detail by CRA/Rio Tinto in the Wickepin
area, 180km south-east of Perth. These were acquired some years
ago by WA Kaolin Holdings Pty Ltd (WAK).
From 1994 until 1996, 601 holes were drilled with 220 holes
drilled in 2003-04 (a total of almost 20,000 metres of drilling
core) and further drilling carried out by WAK and by CVRD
(Brazil). Extensive resources have been outlined and a mining
license on one area covering 10 km2 was granted.
Detailed characterisation studies of the deposit have been
carried out at UK, Japanese, Brazilian and US laboratories, and
a potential high brightness (>90 ISO brightness) delaminated
clay (high aspect ratio) for the Asian market has been
identified. A plant was established at Kwinana but
production was limited and with excess of coating clay being
produced globally, there was little appetite for investment by
In 2016 WAK will complete the construction of a new 20,000
tonne processing plant at Kwinana for its K99 product for
ceramics, fiberglass and as a precursor for refining into
premium paper coating grades for selected customers.
Commissioning is underway and plans startup in October
2016. Views of the K99 dry process plant are shown in Figures 9
The plant is mostly sized for 200,000 tonnes when the plant
is relocated to the mine site by mid 2017. Marketing will start
immediately after startup.
|Figure 9: 50 tph clay feeder to K99 Dry
|Figure 10: K99 - Dry Process Plant
Kaolin and proppants in the US
Ceramic proppant producers in the US are experiencing a
downturn in the market at present on the back of sluggish oil
and gas exploration.
Carbo Ceramics Inc (five plants), Imerys Oilfied Soultions
(two plants) and Saint Gobain Proppants (two plants) are the
three main producers in the country.
Saint Gobain utilises bauxite as its feedstock, but Carbo
uses bauxite, kaolin and alumina and Imerys only uses
Imerys announced in July 2011 the inauguration in
Andersonville, Gerogia a production unit for ceramic proppants
which was commissioned in 2013. Imerys were already
active in this market with rod shaped proppants (PropyniteTM)
and mineral additives. The proppant production unit represented
an investment of around $60m, and was built on the
Andersonville site. The Andersite built up capacity of over
220m lbs pa of ceramic proppants.
In April 2013 Imerys purchased PyraMax Ceramics LLC, which
was in the process of constructing and completing a plant in
Wrens (Georgia) for ceramic proppants. The plant had two
production lines and would be gradually ramped up during 2014
for a total annual capacity of 225,000 tonnes with an
investment of $235m.
When the factory was being constructed, project managers
said the Wrens plant’s total proppant capacity was
seven rail cars per day and that the 10 silos they had planned
could contain 2.8m lbs of capacity each, a total of 14,400
tonnes or 20 days of production.
Current capacity is 500 m.lbs pa giving a total of 720 m.lbs
pa with the Andersonville plant.
In late February 2015 Imerys announced it would idle its
facility in Andersonville, Georgia and reduce production at the
Wrens plant due to oil prices dropping from $108 a barrel to
$50 a barrel in about eight months.
Carbo Ceramics proppants are made by grinding or dispersing
ore to a fine powder, combining the powder into small pellets
and firing the pellets in a rotary kiln. The company uses
three different methods to produce ceramic proppant. Its
plants in McIntyre, Georgia; Kopeysk, Russia and Luoyang,
China use a dry process, which utilises clay, bauxite,
bauxitic clay or kaolin. The raw material is ground,
pelletized and screened. The manufacturing process is
completed by firing the product in a rotary kiln.
The company’s plants in Eufaula, Alabama,
Toomsboro, Georgia, and Millen, Georgia, use a wet process,
which starts with kaolin that is formed into slurry. The slurry
is then pelletized in a dryer and the pellets are then fired in
a rotary kiln.
The portion of the company’s plant in New
Iberia, Louisiana that manufactures ceramic proppant uses a new
manufacturing process associated with the
Company’s KRYPTOSPHERE product line. In addition,
construction has begun to retrofit another of the
company’s plants with this new process.
The company’s Eufaula, McIntyre, Toomsboro and
Millen facilities primarily use locally mined kaolin for the
production of CARBOLITE® , CARBOECONOPROP® and
Carbo has entered into bilateral contracts for at least 50%
of the Eufaula facility’s and Millen
facility’s annual kaolin requirements.
The Eufaula contract runs through 2017, with options to
extend this agreement for additional three year terms. The
Millen contract, which commenced in July 2014, has an initial
term of five years with options to extend the agreement for an
additional five years.
Carbo has obtained ownership rights in acreage in Wilkinson
County, Georgia, which contains in excess of a 12 year supply
of kaolin for its Georgia facilities based on full capacity
production rates. It has entered into a long-term agreement
with a third party to mine and transport this material at a
fixed price subject to annual adjustment.
The agreement requires Carbo utilise the third party to mine
and transport a majority of the McIntyre and Toomsboro
facility’s annual kaolin requirement.
However, the continuing slowdown in shale oil fields has
prompted Carbo to mothball its proppant manufacturing facility
in McIntyre, Georgia with an annual production capacity of 275m
lbs. Slowing production is to assist in managing cash and
inventory levels. The company deferred the completion of a
second ceramic proppant manufacturing line at its Millen,
Arcilla Mining & Land Co. was started in 1992 in Georgia
and much of its production was used as a feed for Carbo
Ceramics for proppants. The success of the Georgia mining
work led to expansion of the company into kaolin-rich areas
of South Carolina. In 2005, Arcilla moved equipment into
Arkansas for mining of bauxite. Arcilla supplies clay to
three Carbo plants in Alabama and Georgia. Around 2012
Arcilla was mining 3.17m tonnes of kaolin and 272,155 tonnes
of bauxite from all their deposits in the US.
Daniel Flanagan (USGS, Clay Specialist), Professor Wen Lu
(Chengdu, China), Larry Lai (Yie-Lie Enterprise, China), Alf
Baker (WA Kaolin Australia), Pramod Pillai (former GM of EICL
and Ashapura, India), Sankameeswaran Shanmugam and JP Dave
(MS Sawa Clay & Minerals), Frank Hart (First Test
Minerals, UK), Nick Wilshaw (Grinding Solutions, UK) and
Murray Lines (Stratum Consultants).