Dry Bright Wire

Copper wire scrap has been graded informally in the UK metals trade since the late Victorian period, when industrial electrification began pulling vast quantities of copper out of mines and into transformer windings, telegraph lines, and dynamos. The American ISRI grading code "Barley" became the international shorthand for what UK yards call dry bright wire. Barley is defined as clean, unalloyed, uncoated copper wire and cable, no smaller than No. 16 B&S wire gauge — roughly 1.3mm in diameter — free of burnt wire which is brittle, and free of insulation. UK yards apply slightly looser tolerances in practice but the principle is identical. The reason the diameter cut-off exists is purity yield: very thin wire (sometimes called "candy wire" in the trade) has more surface area relative to volume, oxidises faster, and is more likely to have come from low-grade communications or signal cable rather than power transmission. It pays less and is bought as a separate grade.

A few things will drop dry bright wire into a lower-paying grade, usually Heavy Copper or Number Two Copper. Tinned wire is the classic example. A thin layer of tin coating, common on older marine and aerospace cabling, drops the purity from around 99.5% copper down to roughly 98%, and tin coated copper is bought as a separate grade at a discount of around 5–10% to bright. Burnt wire — copper that has been heated to remove insulation — is unwelcome. The heat oxidises the copper, makes it brittle, and any plastic residue further contaminates the melt. Burning cable insulation is also illegal under the Environmental Protection Act 1990 and the resultant fumes are highly toxic. Yards routinely refuse burnt wire or buy it at a heavy discount. Other downgrades include green oxidation (longer-term moisture exposure), visible flaking, embedded plastic fragments from poor granulation, mixed-in solder, and any tarnish darker than the normal pinky-orange. None of these things make the copper worthless — but they push it down to Number Two grade, which typically pays 15–25% less per tonne than dry bright.

A few practical things. Sort your wire properly before you come in. If you have a mixture of stripped and unstripped, separate it — the unstripped will be paid as cable (much less per tonne) and contaminating your bright wire bag with insulated lengths will downgrade the whole load. Keep it dry from the moment you strip it. If you are doing volume, invest in a covered storage area — a cheap polytunnel will pay for itself in months. Do not burn insulation, ever. If you cannot strip cable cleanly by hand, sell it as unstripped — yards have granulation contracts that will recover the copper properly and you will end up better off than burning it and selling oxidised wire. Do not store it on a concrete floor outdoors where it can absorb moisture and tarnish. If you bring in a couple of bags of mixed lengths, do not be surprised if the yard checks the bottom of the bag — historically some sellers tried to load the top with bright and bury contaminated wire underneath. Yards know the trick and they will tip the bag out to look.

LME copper has been on a structurally upward trend over 2021–2026, with significant volatility along the way. The cash settlement price began 2021 at roughly $7,800/tonne, peaked above $13,000 in early 2026, and has spent extended periods between $8,000 and $11,000. The drivers are no secret in the trade: electric vehicles use three to four times the copper of an internal combustion car, every kilowatt of new solar PV needs around 4kg of copper, grid upgrades to handle renewable connection are massively copper-intensive, and global mine supply has struggled to keep up. Goldman Sachs and the major broker houses are forecasting continued upward pressure, with mid-$10,000 to $15,000 ranges projected for the late 2020s. Sterling weakness against the dollar adds to what UK scrap yards can pay because LME copper is priced in dollars but UK transactions clear in pounds. None of this means dry bright wire never falls in price — it absolutely does, sometimes 10% in a week — but the longer trend has been upward.