PEA
An early, rough-and-ready estimate of whether a mineral project might be worth developing, before anyone has done the detailed engineering work.
तकनीकी रूप से: A Preliminary Economic Assessment is a study that includes an initial assessment of the potential viability of a mineral deposit, typically completed at an order-of-magnitude level of cost accuracy and before a pre-feasibility study. Uniquely among the study levels, a PEA is permitted under most reporting codes to incorporate inferred resources in its economic analysis, provided appropriate caveats are disclosed. Because of its lower engineering maturity and the inclusion of less-certain resource categories, a PEA cannot be used to support a reserve declaration or a production financing decision.
Markets
pegmatite
An igneous rock with exceptionally large crystals — sometimes as long as your arm. Pegmatites often contain unusual elements like lithium, caesium, and rare-earth metals that got concentrated into the last fluids as a magma cooled.
तकनीकी रूप से: Pegmatite is an intrusive igneous rock characterised by an extremely coarse crystal size, conventionally with a median grain size exceeding a few centimetres, formed from volatile-enriched residual melts or fluxed crystallisation in the final stages of magmatic cooling. The high concentrations of water, fluorine, boron, and lithium in these residual melts allow rare and large-ion-lithophile elements — lithium, caesium, rubidium, beryllium, tantalum, niobium, tin, and rare earths — to reach exploitable concentrations. Lithium-caesium-tantalum (LCT) pegmatites are the principal hard-rock source of lithium globally and are distinguished from the niobium-yttrium-fluorine (NYF) family by their geochemical affinity and tectonic setting.
Geology
placer deposit
A natural concentration of heavy or tough minerals that have been washed out of older rocks and settled in a riverbed, beach, or ancient valley floor, much like gold settling to the bottom of a prospector's pan.
तकनीकी रूप से: A placer deposit forms when weathering liberates resistant, dense minerals from their source rocks and flowing water, wind, or wave action sorts and concentrates them by specific gravity. Economically significant placers include alluvial (river), eluvial (hillslope), and marine shoreline varieties. The term is sometimes loosely applied to aeolian concentrations, but strictly these require separate qualification because the sorting mechanism differs from hydraulic settling.
Geology
platinum-group metal
A family of six rare silvery metals — including platinum, palladium and rhodium — that share similar properties and are often found together in the same rocks.
तकनीकी रूप से: The platinum-group metals (PGMs) are platinum, palladium, rhodium, ruthenium, iridium and osmium, grouped together on the basis of shared geochemical behaviour, mutual occurrence in the same sulphide ore bodies, and broadly similar physical and catalytic properties. They are extracted principally as co-products or by-products of nickel and copper sulphide mining. Because PGMs partition differently within an ore and into different refinery streams, their individual supply ratios are largely fixed by geology and cannot be adjusted independently of one another.
Materials
polysilicon
Extremely pure silicon made by refining ordinary silicon through chemical processes until it is clean enough to be used in solar panels and computer chips.
तकनीकी रूप से: Polysilicon, or polycrystalline silicon, is silicon refined to a purity that removes nearly all metallic and non-metallic impurities, typically through conversion of metallurgical-grade silicon to a gaseous intermediate such as trichlorosilane, followed by chemical vapour deposition. The resulting material is polycrystalline in structure and serves as the feedstock for both the Czochralski process, which produces monocrystalline silicon wafers for semiconductors and high-efficiency solar cells, and for direct casting of multicrystalline ingots used in standard photovoltaic modules. Polysilicon should not be confused with metallurgical-grade silicon, from which it is derived but which is of substantially lower purity and commands a different price.
Materials
porphyry
A type of igneous rock that has large crystals scattered through a finer-grained background, like chocolate chips in a biscuit. Several of the world's biggest copper and gold mines are found in porphyry rock.
तकनीकी रूप से: In economic geology, porphyry refers both to the igneous rock texture — phenocrysts set in an aphanitic or fine-grained groundmass — and to a class of large, low-grade, disseminated metal deposits genetically linked to shallow intrusions of porphyritic composition. Porphyry copper deposits, which may also carry molybdenum, gold, or silver, are typically of low grade but very large tonnage, with mineralisation distributed through a network of stockwork veins and fractures rather than in discrete high-grade shoots. They are distinguished from skarn and epithermal deposits by their intrusion-centred, stockwork-controlled geometry and broadly calc-alkaline host magmatism.
Geology
precious metal
Metals like gold, silver and platinum that are rare, do not corrode easily and have historically been used as money or jewellery as well as in industry.
तकनीकी रूप से: Precious metals are those with high economic value per unit mass, arising from a combination of relative scarcity, chemical resistance to corrosion, and sustained demand for monetary, ornamental and industrial uses. Gold, silver and the platinum-group metals are the standard members of this category. The distinction from base metals is partly chemical — precious metals are nobler and more resistant to oxidation — but is equally a market convention reflected in separate trading, pricing and custody arrangements.
Materials
precursor
A material that has been prepared partway through a process and is ready to be turned into the final product — like a cake mix that still needs baking.
तकनीकी रूप से: In materials processing, a precursor is an intermediate compound manufactured to a controlled specification and intended as the direct feed for a subsequent reaction that yields the end product. In lithium-ion battery supply chains the term most commonly refers to precursor cathode active material (PCAM) — typically a co-precipitated mixed hydroxide of nickel, manganese, and cobalt — which is blended with a lithium source and calcined to produce cathode active material. Confusion arises because 'precursor' is used across many industries with slightly different scopes; the battery-industry sense is narrower and more chemically specific than the general industrial usage.
Processing
probable reserve
Ore that experts are fairly sure can be mined at a profit, though with a little less certainty than a proven reserve.
तकनीकी रूप से: A probable reserve is derived from at least an indicated resource, with modifying factors applied and economic viability demonstrated through a pre-feasibility or feasibility study, but with somewhat less geological or technical certainty than a proven reserve. In practice, probable reserves often constitute the majority of a mine's declared reserves. The distinction from proven reserves matters in financing and reporting contexts, where lenders or regulators may weight the two categories differently.
Markets
prospect
A prospect is a place where geologists have found enough signs of valuable minerals to investigate further, but where no one yet knows whether there is enough to mine.
तकनीकी रूप से: A prospect is an area of mineralisation interest that has been identified by surface sampling, mapping, or geophysical surveys and has received some exploratory attention, but which has not yet been sufficiently drilled or tested to support a mineral resource estimate under any recognised reporting code. It sits between a raw anomaly, which is merely a measurement departure, and a deposit, which has defined mineralisation geometry and grade continuity. The term carries no implication of economic viability; conflating prospect with deposit or resource is a common and consequential error in non-technical communication.
Geology
proven reserve
The most certain kind of minable ore: engineers have checked it very carefully and are confident it can be dug up and sold at a profit.
तकनीकी रूप से: A proven reserve is the highest-confidence category of mineral reserve, derived from a measured resource after the application of modifying factors—including mining, metallurgical, economic, marketing, legal, environmental, social and governmental considerations—demonstrated through a feasibility study. Because it requires both high geological confidence and demonstrated economic viability, the proven category is typically smaller in tonnage than probable or inferred categories. It is the figure most directly relevant to mine life and financing decisions.
Markets
pyrometallurgy
Extracting or refining metals using very high heat — think of a furnace hot enough to melt rock — to separate the metal from everything else.
तकनीकी रूप से: Pyrometallurgy covers the high-temperature processing operations — including smelting, roasting, calcination, sintering and converting — used to extract metals from ores or concentrates and to refine crude metal. Reactions occur in solid, liquid or gas phases at temperatures typically ranging from a few hundred to well over a thousand degrees Celsius. The approach contrasts with hydrometallurgy in that separation relies on differences in melting points, oxidation potentials and slag–matte–metal phase equilibria rather than on aqueous chemistry; in practice many industrial flowsheets use pyrometallurgical and hydrometallurgical stages in series.
Processing