Platinum rod is refined platinum (Pt, atomic number 78, CAS 7440-06-4) drawn or ground into round bar stock, sold at 99.95% to 99.99% purity for use as electrode and contact material, anode stock and further-machined components. Which grade a buyer needs depends on whether the rod becomes a working electrode, an alloyed contact, or feedstock for machining, and the fabrication premium on top of the metal value depends on the same choice. This page covers platinum rod's purity grades, how it is made, what it is used for, and how its price is built on the live platinum (Pt), element 78 value, alongside the wider range of PGM products sold as sponge, powder, wire, foil and gauze.
What Is Platinum Rod?#
Platinum rod is platinum drawn or centerless-ground to a round cross-section bar, distinct from platinum wire mainly in diameter rather than in composition: wire is drawn to fine, flexible gauges for winding and weaving, while rod is supplied as a stiffer, larger-diameter bar for machining, electrode mounting and further fabrication. Sigma-Aldrich, for example, lists a 99.99%-purity platinum rod at 6.0 mm diameter under CAS 7440-06-4, and ESPI Metals lists a 0.25-inch-diameter 4N rod, both illustrating the diameter range fabricators cut rod stock to rather than a single fixed size.
Platinum Rod Purity Grades and Specifications#
Platinum rod ships from 99.95% to 99.99% documented purity, with a published ASTM standard covering both grades. ASTM B561, the Standard Specification for Refined Platinum, covers refined platinum as sponge, cast bar and wrought forms, which includes rod, in two grades: Grade 99.95 (UNS P04995, total impurities of 500 parts per million or less) and Grade 99.99 (100 ppm or less). The impurities the specification actually controls are mostly the other platinum group metals, rhodium, palladium, ruthenium and iridium, because they sit chemically closest to platinum and are hardest to separate from it, alongside base-metal contaminants such as lead, iron and copper that can embrittle the finished bar.
| Grade | Max total impurities | Standard | Typical use |
|---|---|---|---|
| 99.95% (3N5) | ≤500 ppm | ASTM B561 Grade 99.95 (UNS P04995) | General fabrication, anode and contact stock |
| 99.99% (4N) | ≤100 ppm | ASTM B561 Grade 99.99 | Laboratory electrodes, catalyst precursor stock |
Platinum-iridium rod is a separate, alloyed product: ASTM B684/B684M covers two platinum-iridium alloys supplied as rod, wire, strip and sheet, specifying platinum, iridium, total impurities and total other-platinum-group content rather than a single fineness figure.
How Platinum Rod Is Manufactured#
Platinum rod starts from refined platinum sponge, a porous form produced by hydrogen reduction of a precipitated platinum salt to a minimum of 99.95% purity, or from a cast or pressed-and-sintered ingot, per Umicore's own description of its precious-metals output. Fabricators then draw, swage or centerless-grind that starting stock down to the rod's finished round section and length, the same reduction route wire mills use to bring cast or sintered platinum down to fine wire gauges. The as-drawn rod is typically supplied in an annealed temper so it can be bent, welded or further machined without cracking.
What Is Platinum Rod Used For?#
Platinum rod's primary use is as stock for electrodes, anodes and further-machined laboratory and industrial components. Its round cross-section suits it to mounting as a rigid electrode lead or counter-electrode, to machining into anode segments, and to cutting into blanks for pins, probes and instrument parts, uses that draw on platinum's combination of ductility, electrical conductivity and resistance to oxidation. Where the application calls for a harder, more wear-resistant bar than pure platinum offers, fabricators supply platinum-iridium rod instead, built to the ASTM B684/B684M electrical-contact specification described above.
Platinum Rod Price Basis#
The price of platinum rod is the platinum metal value at order time, plus a fabrication premium.
Platinum Rod price = (platinum spot price per troy ounce / 31.1034768) x weight in grams
+ fabrication premium (form, dimension, purity grade, order quantity)
No premium percentage is stated unless a sourced figure exists for this exact form.
The metal-value leg tracks the live platinum spot price, quoted per troy ounce, per gram and per kilogram; the fabrication premium on top of it depends on diameter, grade, order quantity and whether the rod is pure platinum or a platinum-iridium alloy, and no single premium percentage is published for this form.
Platinum Rod as an Electrode#
Platinum rod is used as an electrode because platinum resists oxidation across most electrolytes better than almost any other metal, giving it what the catalysis literature calls the best all-round oxidation resistance among the six platinum group metals, together with unmatched hydrogen evolution and hydrogen oxidation activity. That combination is why plain platinum rod serves as a working, counter or reference electrode in general electrochemistry, while platinum-iridium rod is chosen where the electrode also needs to resist wear, the same alloying trade-off used in the historic Pt-10Ir international prototype kilogram, where iridium raised hardness while preserving platinum's oxidation resistance.
| Metal (electrode form) | Typical electrode role | Why this metal |
|---|---|---|
| Platinum rod | Working, counter and reference electrodes in general electrochemistry | Best all-round oxidation resistance among the six PGMs, with unmatched hydrogen evolution and oxidation activity |
| Platinum-iridium rod (ASTM B684) | Higher-hardness electrical contacts and fine-tip electrodes | Iridium raises hardness and wear resistance while the alloy keeps platinum's oxidation resistance |
| Iridium oxide anode | Anodes for acidic oxygen evolution, such as PEM electrolyzers | The only PGM oxide that survives acidic oxygen-evolution potentials over the long term |
| Ruthenium oxide anode | Dimensionally stable anodes for chlor-alkali electrolysis | Most active oxygen-evolution metal, though it is displaced from long-term acidic duty by volatile oxide loss above roughly 800°C |
Where to Buy Platinum Rod and Supplier Types#
Platinum rod is sold by three overlapping supplier categories, each pricing against the live platinum value plus its own fabrication premium: refiner-fabricators that also sell sponge, powder and wire from the same purity stock, scientific-instrument suppliers that stock small-diameter, high-purity rod for laboratory electrodes, and specialty metal distributors that cut rod to length and diameter for machine shops and equipment builders. Buyers should specify grade, diameter, length and whether pure platinum or a platinum-iridium alloy is required, since the fabrication premium, not the metal value, is where these supplier categories differ most.
Where Platinum Rod Content Stops: Jewelry Retail and Converter Repair#
This page covers platinum rod as an industrial and laboratory material, not ring buying or converter repair. Platinum jewelry alloys and hallmarking sit on the site's jewelry and investment pages, and catalytic converter servicing is outside DailyPlatinum's scope entirely.
Other Platinum Product Forms#
Platinum rod is one of several fabricated forms sold from the same refined metal, each cut to a different cross-section for a different duty. Sibling forms include platinum foil, platinum wire, platinum electrodes, platinum anodes and platinum tubing. The same rod form is also sold in other platinum group metals, including palladium rod, iridium rod and osmium rod, where iridium rod in particular trades on the metal's much higher melting point rather than on electrode duty.
Platinum Price and Market#
Platinum's live spot price and its supply and demand balance sit on their own pages, including the metal's wider market page, rather than being repeated here.
FAQ#
Where can I find platinum rod? Refiner-fabricators, scientific-instrument suppliers and specialty metal distributors all stock platinum rod, generally in the purity grades and diameters set out above.
What is a platinum electrode used for? A platinum electrode carries current into or out of an electrolyte in electrochemistry and electrolysis, chosen because platinum resists oxidation in most electrolytes better than almost any other metal.
What is a platinum iridium rod? A platinum-iridium rod is a platinum-iridium alloy bar built to the ASTM B684/B684M electrical-contact specification, harder and more wear-resistant than pure platinum rod while keeping platinum's oxidation resistance.
Is platinum the strongest metal on Earth? No. On the Mohs scale platinum rates 3.5, softer than every other platinum group metal and far softer than the hardest engineering metals; see platinum's own element page for its full property set.
What is 1 lb of platinum worth? That depends on the live spot price at the time of the question; see the platinum price page for the current per-ounce, per-gram and per-kilogram value rather than a fixed figure here.
What does vinegar do to platinum? Nothing measurable. Platinum is one of the most chemically inert metals in common use and is not attacked by weak acids such as vinegar, only by a small number of strong oxidizing conditions.