Minerals and Metals
Our core products:
The following is a complete listing of the metallic elements that we deal with. We specialize in the minerals of the refractory of high temperature metals.
We deal with these elements in a variety of forms from the mineral concentrates and ores, massive metals, ingots and cathodes, chemical products ,oxides, sulphates, and finally as scrap.
Reflecting our core interests Stapleford Trading is a member of the Minor Metals Trade Association and the Tantalum Niobium International Study Center
Cassiterite
Cassiterite is the primary ore of Tin and forms in high temperature hydrothermal veins, and some contact metamorphic rocks. It is frequently found concentrated in alluvial placer deposits. The chemical unit of Cassiterite is Tin (IV) Oxide, the unit formula being SnO2. Cassiterite forms tetragonal crystal systems, which are brown to black in colour, 6-7/10 on the Mohs hardness scale with a specific gravity of 7.
The price of Cassiterite is made by reference to the amount of Tin metal contained by weight. Typically the London Metal Exchange 3 month US Dollar Official futures price for a metric tonne of 99.85% tin, or the Kuala Lumpur Tin Market daily price, is used as a reference, with a suitable deduction taken to price Tin contained in Cassiterite per tonne. This deduction accounts for costs of transport, conversion of Tin contained in ore into Tin metal.
Our traded Cassiterite is physically processed from run of mine ore to give higher Tin content and minimal amounts of deleterious impurities. Typical specifications are include a percentage by weight of Tin of greater than 65%, and a combined impurities of Fe, Mn, and WO4 of less than 3.5% by weight. Other deleterious impurities such as (but not limited to) Sulphur, Arsenic, and Lead should be as low as possible.
Columbite
Columbite is an ore of niobium, forming a series with tantalite, and forming in granitic pegmatites. The general formula for the chemical unit of columbite is (Fe,Mn)(Nb,Ta)2 O6. The crystal systems are orthorhombic and the colour is black/brown. Thet are rated 6 on the Mohs scale for hardness and have a specific gravity between 5.3 and 7.3. Niobium is also found in the ore pyrochlore. This ore forms again a series with a tantualum rich member – microlite. The general unit formula of pyrochlore is (Na,Ca)2 Nb2O6(OH,F). The crystal systems are isometric, with colour from brown through yellow/red-brown, orange and black. The hardness is 5-5.5 on the Mohs scale, and the specific gravity is 4.45 – 4.9.
The pricing of columbite is done on the basis of the combined amount of niobium contained, measured as diniobium pentoxide (Nb2O5) and the tantalum contained measured as ditantalum pentoxide (Ta2O5). The two pentoxides are summed to give the combined pentoxide (CPO) total, usually expressed as a percent by weight, but also readily converted to pounds of CPO. The internationally traded price is mainly quoted in US dollars per pound CPO. There is no exchange trading of niobium, and price is determined by negotiations between buyers and sellers.
Our traded columbite is physically processed to attain a CPO of > 50% typically. The average percentages by mass of niobium and tantalum pentoxide contained are 48.84% and 4.88% respectively.
Copper
Copper is a group 11, period 4, d-block element with standard atomic weight 63.546. Copper is the best non-precious metal conductor of electricity, transfers heat well, and malleable and ductile. Through alloying, it can extend its properties further.
Major product categories of internationally traded copper include: concentrates, blister, anode, cathode and ingots, semis, and of course scrap of many descriptions.
Copper, either elemental or alloyed, finds use in buildings construction, for electrics, plumbing, and architecture, in infrastructure in electrical and telecommunication applications, and in equipment manufacture for industry, transportation, consumer products, electronics and cooling equipment.
The price paid for a copper containing product is made by reference to the price on an exchange such as the London Metal Exchange, in this case the price for one metric ton of grade A/Grade 1 ingot. the price paid will be a percentage of the exchange price, depending on the percentage of copper contained in the product, and the impurities and format.
Niobium Pentoxide
Our Niobium Pentoxide is sold for and on behalf of the producer by Stapleford Trading Ltd acting as an agent.
Tantalite
Tantalite is the primary ore source of tantalum. It has the unit formula (Fe,Mn)Ta2O6 and forms a series with columbite. The crystal system is orthorhombic and the colour ranges from black through brown to red/brown. Its hardness is 6-6.5 on the Mohs scale and the specific gravity is around 8. Microlite is a tantalum containing mineral, forming a series with pyrochlore. The general formula for Microlite is (Na,Ca)2Ta2O6(O,OH,F). it has a black, through red/brown to yellow colour, has a Mohs hardness of 5.5, and a specific gravity of 4.2-6.4.
The value of Tantalite is determined by the content of Ta2O5, measured in pounds (lb), with a price paid in US dollars per pound of Ta2O5 contained. No additional value is paid for any niobium pentoxide contained. There is no trading on tantalum on exchange, and price is determined by negotiation between buyer and seller.
Our traded tantalite is physically processed and typically contains > 30% tantalum pentoxide, with a mean niobium pentoxide content of 25%, Sb < 20 ppm, and WO3 < 0.5% by mass.
Tantalum Pentoxide
Our Niobium Pentoxide is sold for and on behalf of the producer by Stapleford Trading Ltd acting as an agent.
Tin
Tin is a group 14, period 5, p-block element with relative atomic mass 118.71. Elemental tin can exist in four allotropes. beta-tin (metallic, white tin) is soft and malleable, around 13.2 degrees centigrade beta-tin begin to transform to alpha-tin (grey tin) which has none of the metallic properties owing to a covalently bonded structure, and is a powdery material. Other allotropes exist at temperatures and pressures far above standard. It should be noted that impurities and additions of other elements reduced the temperature at which allotrope transition occurs and with bismuth or antimony addition, the alpha transformation may not occur at all.
Tin (metallic, beta) finds uses in coatings, to prevent corrosion as in tin plated steel cans, and because it takes a high polish. Tin is alloyed with niobium for use in superconducting magnets, and is also used in soft and lead free solder, and found in pewter, and bronze. In window glass manufacture molten tin is used as a float. Tin chemicals such as tin (II) chloride are used in the dye industry, tin (IV) oxide is used in the ceramics and sensor industry, and in Plastics industry zinc tin oxide is used as a flame and smoke retardant. Alpha tin has few applications save for limited uses in semiconductors.
Traded tin products are priced with reference to one of the exchange prices; we use the London Metal Exchange prices which are for a metric tonne of 99.85% minimum purity tin (BS EN 610:1996 standard) in warehouse. The price paid by a buyer will depend on the quality of tin, the format and the location, with adjustments made over or under the exchange price depending on these factors.
Our traded tin is LME brand registered tin ingots; toll converted or produced by Malaysia Smelting Company Berhad, typically 99.85% min Sn content. In addition we can supply higher purity South-East Asian origin tin ingots and wire.
Wolframite and Sheelite
Wolframite and Scheelite are the main ores of Tungsten.
Wolframite forms in quartz veins of granitic pegmatites, being of magmatic or hydrothermal origin. Wolframite is general term for iron and manganese tungstates being the intermediate member of the Ferberite-Hübnerite solid solution series of minerals and given the unit formula (Fe,Mn)WO4. A mineral with more than 80% FeWO4 can be termed Ferberite, and with more than 80% MnWO4 can be termed Hübnerite. The wolframite mineral forms monoclinic crystal systems, ranging in colour from grey/black (Ferberite) to through brown/red black to dark red (Hübnerite). The hardness is 4-4.5 Mohs, and the specific gravity 7-7.5.
Scheelite, CaWO4, forms a solid solution series with Powelite (CaMoO4). If a tungsten containing hyrothermal liquid is in contact with calcium containing rocks, for example limestone (CaCO3) scheelite will form. The Sheelite mineral forms Tetragonal crystal systems, the colour ranges from colourless, through white to yellow and grey. The hardness is 4.5-5 Mohs, and the specific gravity 5.9-6.1. Pure Scheelite has a blue-white fluorescence in Ultraviolet light. Increasing Molybdenum content will give progressively more yellow fluorescence.
The value of Tungsten ores is determined on a US Dollar price per Metric Ton Unit (corresponding to 10kg) of WO3 contained
Typically Russian and Chinese traded ore contains a minimum of 65% WO3 by weight; 50% WO3 by weight is the typical minimum of tungsten ore of African origin. Traded Ore should contain low amounts of CaO on analysis, the presence of which indicates a quantity of Scheelite. Molybdenum content should be kept as low as possible in all traded ores; this is of particular note for scheelite which in the natural state can contain up to several percent Molybdenum. Silicon content should be below 10% measured as Silicon (IV) Oxide. Other impurities such as Iron and Phosphorous should be at a minimum.
Non-Ferrous Scrap
We source a variety of non-ferrous scrap including auto-radiators (Ocean) and lead jumbos.
