This information has not been updated since 2013 and is provided for general reference purposes. For the latest data, please see Australia's Identified Mineral Resources 2016.
Tin (Sn) is used in solders for joining metals and pipes, as a coating for steel cans and in metal alloys. The largest single application for tin is in solders, which accounts for about half of current world consumption. Solders are used in light engineering applications such as plumbing and sheet metal work, in the motor vehicle industry and in cans for various uses. Another major application for tin is coating steel sheet in the manufacture of tinplate, which accounts for about 16% of world tin consumption. Tinplate is used for containers in the form of tin cans for food products, drinks, oils, paints, disinfectants and chemicals.
Australia¿s Economic Demonstrated Resources (EDR) of tin was 277 kilotonnes (kt) at December 2012, up from 243 kt in 2011. Increases in Australia¿s EDR were reported at both the Renison Bell and Mount Lindsay deposits in Tasmania (Tas).
Almost 75% of Australia¿s EDR of tin are contained in the Renison Bell deposit in western Tas. Others include the Mount Lindsay and Queen Hill deposits in western Tasmania. There are several occurrences also in north Queensland (Qld), including the Gillian and associated deposits, and the Mount Garnet and Baal Gammon deposits.
In 2012, Subeconomic Demonstrated Resources (comprising Paramarginal and Submarginal Resources) increased to 96 kt, largely because of reclassification of existing resources. Inferred Resources increased from 231 kt in 2011 to 262 kt in 2012. Tasmania accounts for 49% of Inferred Resources, followed by New South Wales (NSW) with 24% and Qld with 21%.
All of Australia¿s EDR for tin are accessible.
Joint Ore Reserve Committee (JORC) Code reserves comprise total tin in Proved and Probable Ore Reserves as defined in the JORC Code. In 2012, JORC Code reserves of 170 kt accounted for about 61% of Accessible Economic Demonstrated Resources (AEDR). This compares with 119 kt of JORC Code reserves in 2011.
Exploration continued in the historic tin mining areas of Herberton-Mount Garnet in north Qld, in the New England and Bourke regions of NSW and in western Tasmania. Data on tin exploration expenditures are not reported by the Australian Bureau of Statistics.
Australia¿s mine production in 2012 was 58001 tonnes of tin-in-concentrate, an increase from the 2011 production of 5000 tonnes. There has been no production of refined tin in Australia since 2007 when the Greenbushes tin smelter in Western Australia (WA) closed. Total exports of tin for 2012 were 5706 tonnes valued at $110 million2. This compares with 4992 tonnes valued at $118 million exported in 2011.
World economic resources of tin in 2012 are estimated to be 4947 kt based on United States Geological Survey (USGS) data and updated by Geoscience Australia for Australia¿s resources. This compares with 4863 kt of tin resources in 2011. According to the USGS, China holds about 30% of the resources followed by Indonesia with about 16% and Brazil with about 14%. Based on the USGS figures and those updated by Geoscience Australia, Australia has a 5.6% share of world resources of tin.
Based on USGS data updated with Australia¿s production data world production of tin in 2012 is estimated to be 228 kt. These figures represent a decrease on production of 250 kt of tin in 2011. China was the major producer with about 44% of world production, followed by Indonesia with about 18% and Peru with about 13%. USA production was not recorded for confidential reasons. Australian production of 5.8 kt of tin was ranked number seven in the world.
The price of tin on the London Metal Exchange had recovered significantly from the late 2008¿early 2009 low point experienced during the global financial crisis (US$10 000 a tonne or A$14 400), reaching highs (US$33 000 or around A$33 000) in the second half of the 2010-11 financial year. Since then the price has been through a couple of cycles, dropping to below US$18 000 in August 2012, before rising to more than US$24 000 in early 2013, and dropping again to around US$20 000 in mid-2013. It has since recovered to around US$23 000.
In September 2013, Metals X Limited (Metals X) announced a 31% increase in JORC Code resources at the Renison Bell deposit, near Zeehan in western Tas. The resource includes Measured Resources of 1246 kt at 2.22% Sn, Indicated Resources of 6453 kt at 1.57% Sn and Inferred Resources of 3870 kt at 1.93% Sn, for a contained 204 kt of Sn. As at 30 June 2013, the resource includes Proved Reserves of 788 kt at 1.50% Sn and Probable Reserves of 3349 kt at 1.23% Sn for a contained 53 kt of Sn. Renison Bell also has total copper (Cu) resources of 34 kt and total copper ore reserves of 11 kt. The Renison Bell mine, along with the Renison Tin Concentrator, the Renison Expansion Project, Rentails, and the Mount Bischoff Tin Project, all form part of a group of Tasmanian tin assets. These assets are owned jointly (50:50) by Metals X and YT Parksong Australia Holding Pty Ltd, the latter of which is a partnership between Yunnan Tin Group, China¿s largest tin producer and the Hong Kong-based company, L¿Sea Resources International Holdings Ltd (previously known as Goodtop Tin International Holdings Ltd). The assets are managed through the joint venture company Bluestone Mines Tasmania Joint Venture Pty Ltd (BMTJV). Current operations are at the Renison Bell underground mine with ore from the mine treated at the Renison concentrator. Production for 2012 was 5848 tonnes of tin metal and 336 tonnes of copper metal. Renison is aiming for long-term production rates of between 7000 and 7500 tonnes of tin-in-concentrate a year. A copper circuit was commissioned in December 2010, with production of around 500 tonnes a year of copper-in-concentrate. Mining ceased at Mount Bischoffin July 2010 and the last ore was treated in late 2010. The company is carrying out both underground and surface exploration around the Renison deposit. The underground exploration has focussed on the Federal, Deep Huon, Huon North and North King ore zones, as well as delineation and further definition of the Central Federal Bassett zone, which is a recently discovered mineralised zone in the area between the southern and northern declines access.
In 2009, Metals X completed a feasibility study on proposals to recover tin from tailings produced by historic processing of tin ores from Rentails at Renison Bell mine. Resources at Rentails to 30 June 2013 comprise Measured Resources of 20 598 kt averaging 0.45% Sn and 0.21% Cu, which represents 92 700 tonnes of contained Sn and 43 200 tonnes of contained Cu. The resource includes Probable Reserves of 19 757 kt at 0.45% Sn and 0.21% Cu. The recovery project proposes reclaiming tailings at a rate of two million tonnes per annum (Mtpa) to produce about 5300 tonnes Sn and 2000 tonnes copper-in- concentrate a year. Joint venture partners are still working on when the project will be brought into development.
Metals X¿s Collingwood mine, about 30 kilometres south of Cooktown in north Qld, has been under care and maintenance since its closure in mid-2008. The company has indicated that it will dispose of the property.
The Mount Lindsay tin-tungsten deposit is wholly owned by Venture Minerals Limited (Venture). Located 15 kilometres northwest of Renison Bell tin mine and 20 kilometres west of Rosebery in western Tas, the prospect is in magnetite (Fe3O4) rich skarns within the contact aureole of the Meredith granite, which is part of a suite of Devonian¿Early Carboniferous granites that are the source rocks for a number of large tin, tungsten and magnetite deposits in western Tas and on King Island in Bass Strait. The Mount Lindsay tin-tungsten deposit has, as of October 2012, combined resources of 45 million tonnes (Mt) at 0.4% Sn equivalent (with a 0.2% cut-off, 73% of the resource is in the measured and indicated categories) or 13 Mt at 0.7% Sn equivalent at 0.45% cut-off. As of November 2012, reserves included Proven Reserves of 6.4 Mt at 0.2% Sn, 0.2% tungsten oxide (WO3) and 0.1% Cu, and Probable Reserves of 7.3 Mt at 0.2% Sn, 0.1% WO3, and 0.1% Cu, with a contained 30 000 tonnes of Sn. The deposit also includes an iron resource. In late 2012, Venture completed a bankable feasibility study (BFS) for Mount Lindsay which highlighted the long-term potential of the deposit. Highlights of the BFS included a mine life of nine years, a plant capacity of 1.75 Mtpa, a payback period of four years and a capital cost of just under $200 million. The BFS assumed tin prices of US$23 800 a tonne. The company also completed a pilot scale metallurgical program in August 2012 that demonstrated recoveries of 72% Sn and 83% WO3, as well as high grade tungsten concentrate (more than 66% WO3). In August 2012, Venture announced favourable drill intersections from its first hole into the Big Wilson Project approximately six kilometres northeast of the Mount Lindsay Project. Intersections include 35.4 metres at 1.0% Sn, including 17.4 metres at 2.0% Sn and 4.0 metres at 5.6% Sn. The Big Wilson Prospect occurs in an area of historic alluvial tin workings with mineralisation including both skarn and greisen styles.
In January 2012, Stellar Resources Limited (Stellar) took control of the Heemskirk Tin Project through acquisition of joint venture partner Gippsland Limited¿s 40% share of the project. The Heemskirk project, located near Zeehan in western Tas, comprises the Queen Hill, Montana and Severn deposits. The deposits have a combined mineral resource of 6.28 Mt at 1.14% Sn (at February 2013), including Indicated Resources of 1.41 Mt at 1.26% Sn at the Queen Hill deposit. The majority of the resource is in the Severn deposit which has an Inferred Resource of 4.17 Mt at 0.9% Sn. Stellar completed a favourable scoping study for the three deposits in July 2011 which highlighted the potential for an economic underground tin mine. The company completed a positive prefeasibility study in mid-2013 that indicated an initial mine life of seven years with an annual production of around 4300 tonnes of tin-in-concentrate, and a head grade of 1.06% tin. Metallurgical test work on the Heemskirk ores has suggested concentrate grades approaching 48% tin with an overall tin recovery of 70%. The company has indicated that it is targeting additional drilling to expand the resource base and convert resources to reserves, as well as identify a potential tin industry partner to help with progression of the project through a definitive feasibility study.
In mid-2013 the Australian based Elementos Ltd (Elementos) acquired the Cleveland Tin project through a merger with the unlisted Rockwell Minerals Ltd (Rockwell), which previously controlled the project and owned 50% of the asset. The Cleveland project is located 60 kilometres southwest of Burnie in Tas and includes the underground tin-copper Cleveland mine. The mine, which was mined by Aberfoyle Ltd between 1968 and 1986, produced about 23.5 kt of Sn and 9.7 kt of copper-in-concentrate. The mine closed as a result of low tin prices in the late 1980s. The Cleveland project also includes a large low-grade tin-copper tailings dam, as well as the Foley Zone tungsten (W) deposit. The company has indicated it plans to undertake further drilling to test extensions of tin and tungsten mineralisation. In late 2013, Elementos indicated it had initiated a prefeasibility study to assess the development potential of the hard rock and tailings dam tin-copper resources. The study, which is due for completion in the second quarter of 2014, will be based on recently released (April 2013) JORC Code compliant total resource for the Cleveland mine of 6119 kt at 0.68% Sn and 0.25% Cu, containing 42 kt of Sn, of which 4239 kt at 0.70% Sn and 0.28% Cu (contained 30 kt of Sn) are Indicated Resources. Mineralisation at Cleveland is mainly hosted in vertical-dipping semi-massive sulphide lenses replacing limestone. Mineralisation is thought to be related to the nearby Meredith Granite. Tin is present as cassiterite and minor stannite. The tailings dam resource contains Inferred Resources of 3850 kt at 0.30% Sn and 0.13% Cu for a contained 11.6 kt of Sn. Rockwell previously completed an internal scoping study which reportedly demonstrated the reprocessing potential of the tailings. A JORC Code compliant Inferred Resource of 3980 kt at 0.30% WO3, for a contained 12 kt of WO3, has also been calculated for the Foley Zone tungsten deposit. The tungsten occurs as wolframite hosted within a quartz stock-work.
In February and September 2011, TNT Mines Limited applied for offshore exploration tenements in Ringarooma Bay as part of its Ringarooma Bay alluvial tin project in northeast Tas. The tenements cover parts of the old Ringarooma River channel. The project has an historic Indicated Resource of 16 million cubic metres at 227 grams of tin per cubic metre. TNT has undertaken work at its other Tas properties, including initial metallurgical investigations at the undeveloped Moina fluorspar-tin-tungsten deposit which is a magnetite skarn with complex metallurgy in northwest Tas. In July 2013, Niuminco Group Limited (Niuminco) announced that it intended to make a takeover bid for TNT Mines.
In the third quarter of 2011, mining activities commenced at the Monto Minerals Limited (Monto) Baal Gammon polymetallic deposit, seven kilometres west of Herberton in north Qld. Mining was being undertaken by Kagara Limited (Kagara) which has a Minerals Rights Agreement with Monto. The ore was being processed at Kagara¿s Mount Garnet copper processing facility and just under 38 kt of ore with an average grade of 1.9% Cu and 41.5 grams per tonne (g/t) silver (Ag) had been milled prior to suspension of activities by Kagara in April 2012 before the company went into voluntary administration. Prior to cessation of mining, Kagara undertook resource diamond drilling at the deposit and released an updated resource estimate with Indicated Resources of 2769 kt at 1.0% Cu, 40 g/t Ag, 0.2% Sn and 38 g/t indium (In). Tin was not being extracted, but Monto and Kagara were assessing the technical and commercial feasibility of a tin extraction circuit. In January 2013, Kagara announced it had completed the sale of the Kagara group¿s Central Region assets to Snow Peak Mining, which is a subsidiary of Hong Kong investment group Snow Peak International Investment Pty Ltd, and the major shareholder of Consolidated Tin Mines (Consolidated). Assets included resources and the processing plant at Mount Garnet, as well as mining rights for the Baal Gammon mining area. Monto announced in October 2013 that Snow Peak had recommenced mining operations at Baal Gammon in the second half of 2013, with ore to be treated at the Mount Garnet processing plant, expected to begin in the first quarter of 2014. In November 2011, Monto applied successfully for a mining lease over the Confederation copper-tin prospect, contiguous with the existing Baal Gammon Mining Leases and within 800 metres of the Baal Gammon mine. Monto undertook drilling at the Confederation prospect in the first half of 2012. Intercepts included six metres at 4.33% Cu, 1.25% Sn, 106 g/t Ag and 301 g/t In. The Baal Gammon deposit forms part of Monto¿s larger Herberton tin project, centred on the historic tin mining region around, and to the west of, Herberton. A regional (188 square kilometres) soil geochemistry survey of the project area commenced in September 2012 and was about 30% complete by mid-2013. A number of anomalies have been identified. Monto also reported near surface tin mineralisation from its May 2013 drilling program at its Alexandra and Dargo prospects at Mount Ormonde about seven kilometres southwest of Baal Gammon, including six metres at 1.49% Sn and five metres at 1.03% Sn. Follow-up drilling in June 2013 included two metres at 2.61% Sn. Monto also reported interesting poly-metallic anomalies including copper, lead, zinc, arsenic, bismuth, tellurium, tungsten, tin and gold in a deep drill hole at the Zig Zag prospect, also in the Mount Ormonde region.
In September 2013, Consolidated Tin Mines Ltd (Consolidated) announced it had completed a positive prefeasibility study for the Mount Garnet tin project, 200 kilometres southwest of Cairns in north Qld. The Mount Garnet project includes the Gillian, five kilometres southwest of Mount Garnet, and Windemere 25 kilometres northeast of Mount Garnet tin deposits, and prospects in the Coolgarra group area 15 kilometres northeast of Mount Garnet. Highlights of the prefeasibility study included a minimum nine year mine life from a one Mtpa open cut mine producing an average 2994 tonnes per annum (tpa) of tin-in-concentrate, as well as iron (Fe) and fluorine (F). As part of the study, Consolidated released an updated minerals resource estimate in June 2013, with a total JORC Code resource of 13.118 Mt at 0.39% Sn and 22.87% Fe and 7.035 Mt at 5.8% F for its Mount Garnet project. Included within the total resource is a JORC Code Measured Resource for the Gillian deposit of 1.105 Mt at 0.73% Sn and 32.32% Fe. The majority of the tin resource (just over half) is contained within the Pinnacles deposit. The Gillian, Pinnacles and Windemere deposits are in iron-rich skarns adjacent to granitic intrusions, while the Coolgarra area contains sediment-hosted and granite greisen mineralisation. The Mount Garnet skarn deposits contain fine cassiterite which is difficult to recover because of metallurgical problems. During 2011-12 Consolidated undertook metallurgical testing to separate the fine cassiterite from the ironstone skarn material. It also processed an 80 tonne sample from the Gillian Project at the Talison mine site at Greenbushes in WA. Results of the metallurgical testing were incorporated into the prefeasibility study. In October 2013, major shareholder, Snow Peak International Pty Ltd (Snow Peak), indicated it would exercise its option to earn up to 50% interest in a joint venture with Consolidated to develop the Mount Garnet project. The option was based on a 2012 agreement between the two companies for Snow Peak to fund completion of the prefeasibility study. Consolidated has indicated it will use the funding raised from the joint venture options to complete a final phase of drilling at Gillian as part of its definitive feasibility study of the Mount Garnet project. The company also announced in October 2011 that it had reached agreement with Friends Exploration Pty Ltd to purchase the Jeannie River prospect, 92 kilometres northwest of Cooktown in north Qld. On the basis of previous exploration results by Carpentaria Exploration Company, Consolidated announced a JORC Code compliant Inferred Resource of 2240 kt at 0.60% Sn. The Jeannie River prospect comprises parallel cassiterite mineralised quartz veins.
MGT Mining Limited (MGT), which formerly was Xtreme Resources Limited and is an 86.5% owned subsidiary of MGT Resources, continued exploration around the historic tin mines in the immediate proximity of its Mount Veteran tin plant, including the Dalcouth, Summer Hill, and Extended prospects. All are located in the Mount Garnet district in north Qld. An upgrade of the tin plant was completed in 2011 resulting in a 70 000 tpa processing capacity. The company has indicated it is planning an upgrade to the plant to increase processing capacity to 250 000 tpa in 2013¿14, pending discovery of further tin resources. In September 2012, MGT successfully completed pilot runs of the mill. A mining lease was granted in late 2011 for the Heads or Tails lease in the Smiths Creek area about 15 kilometres from the mill and will use mine tailings as feed for the mill, but this has been delayed by environmental requirements. Metallurgical testing has indicated 75% recovery of tin is possible from the tailings. MGT reported that 17 tonnes of around 65% tin-in-concentrate was produced and shipped to an Asian smelter in the first quarter of 2013. Production was, in part, from stockpiles from historic mining but also included material purchased from local miners. The Summer Hills mining lease, which surrounds the Mount Veteran processing plant and lease, was approved in January 2013 and the company has since undertaken three phases of drilling on the lease. Targets included the Dalcouth and Extended prospects. MGT reported favourable shallow tin intercepts from the first two phases of drilling, including 4 metres at 2.24% Sn, and 8 metres at 1.1% Sn.
At Greenbushes mine in southwest WA production of tin ceased with the closure of the smelter in 2007. Tin resources for Greenbushes operations have not been publicly reported for more than a decade. Historical estimates of tin resources for Greenbushes have not been included in Australia¿s EDR since 2008. Global Advanced Metals (GAM) indicates that it has produced by-product tin from its tantalum deposit at Wodgina about 100 kilometres southeast of Port Hedland in WA, but the amounts are not reported. Although production at Wodgina resumed in April 2011, with ore processed at GAM¿s Greenbushes facilities, the mine closed again early 2012 following softening of demand for tantalum.
In 2011-12, Malachite Resources (Malachite) shifted focus, concentrating on its Lorena gold project in northwest Qld. As a result, minimal exploration has been undertaken by the company on its polymetallic Conrad Silver Project 25 kilometres south of Inverell in northeast NSW. The current global resource figures for the Conrad project have Indicated Resources of 447 kt at 123.8 g/t Ag, 0.26% Cu, 1.3% lead (Pb), 0.46% zinc (Zn), 0.28% Sn and 7.7 g/t In, as well as Inferred Resources of 1807 kt at 101.9 g/t Ag, 0.21% Cu, 1.22% Pb, 0.46% Zn, 0.22% Sn and 6.4 g/t In. Tin is present as stannite and cassiterite. A preliminary scoping study into the Conrad deposit highlighted the narrow width of ore zones (largely 0.6 to 0.8 of a metre) and the sensitivity of such to the economics of the deposit. In 2012, Malachite granted an exclusive six-month option to Mancala Resources Pty Ltd (Mancala), a privately-owned Australian mining contractor with narrow vein expertise and vertical mining technology The option allowed Mancala to carry out an evaluation of the Conrad Silver Project and the right, if exercised, to enable it to take a 50% interest in the project by funding and completing a feasibility study. The option was extended by six months to March 2013, and in April 2013 Malachite announced that Mancala was not exercising the option. Based on Mancala¿s review of the project, Malachite indicated that it was considering an RC drilling program at the Princess shoot end of the field testing for near surface mineralisation which, initially, could support a mining operation.
In late 2012, YTC Resources Limited (YTC) announced it had reached agreement with Straits Resources Ltd (Straits) to acquire 100% of the Doradilla tin project. Prior to this, YTC had the right to earn 70% of the Doradilla Project from Templar Resources, a wholly owned subsidiary of Straits, by spending $1.5 million over five years. The Doradilla project, which is 55 kilometres southeast of Bourke in NSW, contains the Doradilla, Midway-East Midway and 3KEL tin deposits. These deposits occur within a linear skarn unit that can be traced for more than 17 kilometres along strike. Mineralisation is thought to be genetically related to the mid Triassic Midway Granite. The resource is limited to the weathered zone (laterite) where tin is hosted in stanniferous goethite, garnets, secondary cassiterite and minor primary cassiterite. The company has announced a combined Inferred Resource for the tin laterite (oxide) mineralisation of 7.81 Mt averaging 0.28% Sn at a cut-off grade of 0.1% Sn for 22.3 kt of contained tin. During 2011, YTC undertook drilling to test the mineralised contact of an intrusion associated with copper-tungsten mineralisation at the historic Doradilla Mine. The company reported broad intervals of anomalous lead and zinc and occasional intervals of anomalous copper, tin and silver. Drilling at Doradilla in the second half of 2012 was undertaken to assess the largely untested oxide zone of the skarn above the Doradilla deposit. Drilling confirmed the presence of tin mineralisation, with the best intercept being 10 metres at 1.09% Sn.
At its Tallebung tin-tungsten deposit 70 kilometres northwest of Condobolin in central NSW, YTC has commenced a Right to Negotiate process under the Native Title Act to obtain access to undertake two deep drill holes to test targets from a previous resistivity survey below outcropping mineralisation and to assist in scoping of the Tallebung system for a potential large tonnage low grade tin deposit. Negotiations were continuing as of November 2013. In the September quarter of 2011, YTC completed a shares and options agreement with Taronga Mines Limited (Taronga Mines) and Australian Oriental Mines for its New England tin projects of Pound Flat and Torrington. Taronga Mines also controlled the adjacent lease over the large, low grade Taronga tin deposit. AusNiCo acquired all of the shares in Taronga Mine in early 2013, including ownership of the Taronga deposit. The company released a maiden JORC Code resource estimate for the deposit in August 2013. Indicated Resources, which include a larger northern zone (19.3 Mt) and a southern zone (7.6 Mt), are 26.9 Mt at 0.17% Sn for a contained 45 kt of Sn. The deposit also has an Inferred Resource of 9.4 Mt at 0.13% Sn for a contained 12.2 kt of Sn. The resource figures also include Inferred Resources of 36.3 Mt at 0.07% Cu and 3.8 g/t Ag, for a contained 26.4 kt of Cu and 4.4 million ounces of Ag. Resource figures were calculated using a 0.1% Sn cut-off. The mineralisation at Taronga, which is about 50 kilometres north of Glen Innes in NSW, occurs as a sheeted vein system with two main zones (northern and southern) of mineralisation about 300 metres apart. Tin occurs predominantly as cassiterite and is largely hosted within quartz vein boundaries. AusNiCo is undertaking an updated prefeasibility study. A prior prefeasibility study for Taronga was completed by Newmont in 1982.
Further exploration at the Prospect Hill Tin Project in the northern Flinders Ranges of South Australia has been postponed indefinitely because of matters associated with Native Title. Havilah Resources, which has earned a 65% interest in the project, had planned further exploration in 2011-12, including drilling aimed at increasing the hard rock resource. The South Ridge prospect within the Prospect Hill project area has old Inferred Resources of 172 000 tonnes at 1.15% Sn.
- Figures do not include tin production in Western Australia for which data is not available. Production in that State is not believed to be significant.
- Export statistics from the Bureau of Resources and Energy Economics, 2013: Resources and Energy Quarterly September 2013.
McKay, A.D., Miezitis, Y., Porritt, K., Britt, A.F., Champion, D.C., Cadman, S., Towner, R., Summerfield, D., Whitaker, A., Huston, D., Jaireth, S., Sexton, M., Schofield, A., Hoatson, D., Senior, A.B. & Carson, L., 2014. Australia's Identified Mineral Resources 2013. Geoscience Australia, Canberra, Australia. http://dx.doi.org/10.11636/1327-1466.2013