Mill Berry Copper Explained: ISRI Barley Grade, Specs & Bulk Pricing

"Mill berry" is one of the most traded — and most misunderstood — terms in the copper market. If you're a refiner, manufacturer, or export buyer sourcing copper in volume, knowing exactly what mill berry is (and what the ISRI Barley code guarantees) is the difference between a clean shipment and a costly downgrade on arrival.

What is mill berry copper?

Mill berry is the trade name for No. 1 bare bright copper wire — clean, uncoated, unalloyed copper wire of high purity. It is recovered from electrical wiring and cable, stripped of all insulation, and free of tin, solder, brass fittings, and other attachments. In the bulk market it is prized because it can be re-melted with minimal processing, which is why refiners and rod mills pay the highest scrap premium for it.

The name comes from the ISRI specification code Barley. Internationally, buyers and sellers use the ISRI code so that "mill berry" means the same thing in Miami as it does in Mumbai or Shenzhen.

ISRI Barley: the specification that matters

ISRI — the Institute of Scrap Recycling Industries — publishes the standard grade codes the global metals trade runs on. The Barley code defines mill berry as:

Clean, untinned, uncoated, unalloyed copper wire and cable, not smaller than No. 16 B&S wire gauge, free of burnt wire that is brittle. Hydraulically briquetted copper subject to agreement.

In practice, "Barley grade" tells your refiner three things at a glance: the copper is bare and bright (no insulation or coating), it is unalloyed (essentially pure copper, not brass or bronze), and it meets a minimum gauge so fines and hair-wire don't drag down the yield.

Mill berry vs. lower copper grades

Mill berry sits at the top of the recovered-copper hierarchy. Below it are grades that carry more contamination and therefore a wider discount to the LME:

• No. 2 copper — unalloyed copper with some coating, solder, or oxidation; typically miscellaneous gauges. Traded under ISRI codes such as Birch/Cliff.
• Insulated copper wire — copper recovered with its plastic jacket; priced on recoverable copper content, not gross weight.
• Mixed wire scrap — varied gauges and conditions, often container-loaded for refiners and recovery operations.

For a full side-by-side of cathode, mill berry, wire scrap, and ingot, see our copper grades guide.

How mill berry is priced

Bulk copper is never sold at a flat dollar figure — it tracks the London Metal Exchange (LME) copper price, which moves daily. Mill berry, as the cleanest grade, earns the smallest discount to that benchmark. At Atlas Copper, sell rates track the LME daily with a transparent processing margin, and volume tiers apply for larger orders. To understand exactly how the benchmark, margin, and tiers combine into your number, read how copper pricing works.

Buying mill berry in bulk from Atlas Copper

Atlas Copper International has supplied bulk copper from Doral, Miami since 1962. For mill berry and other grades:

• Domestic US: minimum one pallet; free FOB haulage to Port Everglades on full-truckload, container-grade orders above minimum order value.
• Export: minimum 5 × 20ft containers (approximately 110–120 metric tonnes depending on grade), shipped FOB Port Everglades / PortMiami, CIF, or CFR worldwide.
• Documentation: grade and weight papers with every order; certified ASTM Mill Test Reports and pre-shipment inspection (SGS, Bureau Veritas, Cotecna) on request.

Frequently asked questions