C68700 Aluminum Brass Prices November 9, 2026

C68700 melt reference = Cu × 0.775 + Zn × 0.202 + Al × 0.0215 + As × 0.0004 (mid-range UNS C68700 chemistry). 1 tonne = 2,204.6 lb; $3,268/tonne zinc = $1.48/lb.

copper's first decline in five weeks would take 2–4 weeks to reach brass quotes, because brass mills buy cathode on their own cycle. Here is the ledger:

Two consequences follow. First, the bigger November 2 copper leg is still worth roughly $0.06–0.08/lb of additional relief on plate, sheet, pipe and bar - it lands between now and November 23. Second, the forms that did not move this week - U-bend tube, strip, and tube sheet - will not move next week either: their pricing is set by press, bending-line and annealing capacity, not by metal. A form that ignored a $0.10/lb copper decline does not suddenly find religion because copper stabilizes.

This is the number most buyers will miss. LME zinc has risen 6.8% over three weeks - from $3,060 to $3,268/tonne - on concentrate tightness and smelter maintenance. At 20.2% of the C68700 melt, that adds back +$0.037/lb while everyone watched copper fall $0.10/lb. Net across the two weeks: melt down $0.07, not $0.08; and once the full November 2 copper leg lands, zinc will have consumed roughly a third of the total relief.

The same arithmetic runs inside the grade comparison. C68700 carries the lowest zinc content of the condenser-brass family at 20.2% - C44300 carries ~28.5%, C46400 ~39%. Every $0.10/lb zinc rally costs a C44300 buyer about $0.014/lb more and a C46400 buyer about $0.020/lb more than a C68700 buyer. Three weeks into a zinc rally, the spec-upgrade math tilts further toward C68700 - roughly $0.03–0.05/lb per equivalent tube size versus C44300, before dezincification performance is even discussed.

Welded B467 pipe remains the fastest value in the family at $9.55–11.10/lb where pressure class allows - about $0.50/lb under seamless B466 with two weeks off the schedule. Third-party witnessed testing adds 2–3 weeks but can be booked in parallel at order entry.

The pending November 2 copper leg is worth about $0.06–0.08/lb on metal-priced forms - on a 20,000 lb annual plate-and-busbar program, $1,200–1,600 that arrives whether you rush or not. On tube, the same $0.06 competes against a 7–10 week queue during the Q4 retube window. The decision splits cleanly:

Plate, sheet, pipe, bar - waiting is cheap and rational. These lines are metal-priced, order books are slack, and the pending leg lands within two weeks. Write "quote valid 14 days with metal-adjustment clause" into the RFQ so the mill passes the November 2 leg through instead of pocketing it. Expected saving on a 10,000 lb order: $600–800.

Seamless condenser tube B111 - book the slot now, price the metal later. Lead times have held at 7–10 weeks for four weeks running, and retube bundles keep arriving. The correct structure is a production-slot order with metal priced at shipment against a published index, capped at −$0.08/+0.08/lb - you keep the pending relief if it arrives and cap your exposure if zinc keeps climbing.

U-bend tube B395 and tube sheet - stop waiting entirely. Three consecutive weeks of $0.00 movement on forms with 8–12 week lead times is capacity pricing, not stubbornness. Every week of delay costs queue position, not money saved: a 700-tube retube quoted November 9 ships late January; quoted November 30, late February.

Welded B543 - the compromise. It took the full −$0.05 relief and still carries a 5–8 week lead time. Where design pressure allows a welded seam, waiting and booking are both defensible here.

Four items keep generating claims:

Velocity stays the design limit, not wall thickness. C68700 handles about 2.4 m/s continuous in seawater. Above that, the answer is C70600 copper-nickel (3.0–3.6 m/s) - not thicker C68700 walls, which erode at the same velocity and only fail later.

Arsenic must appear as an actual value on the EN 10204 3.1 certificate. As 0.02–0.06% is what makes this arsenical aluminum brass; without the printed value you are buying an unspecified grade, not a dezincification guarantee.

Stress relief after bending. U-bends and cold-formed fittings need 300–350°C post-form stress relief, screened per ASTM B858 - unrelieved brass plus ammonia-bearing water is the classic transgranular cracking pair.

No sulfur-bearing cutting fluids on tube-sheet drilling. Sulfur residues undermine the alumina film and seed pitting at ferrule seats. Specify chlorine-free, sulfur-free coolant in the machining note.

Three markers decide whether December brings more relief or a floor: zinc breaking $3,400/tonne flips this grade's melt back to rising even with copper flat; copper holding above $14,000/tonne through mid-November confirms the two-week dip as a correction, and mills slow-walk the remaining pass-through; B111 lead times printing 11 weeks or more would mean the retube window has saturated even slot bookings - at that point, metal-adjacent savings stop mattering entirely.