Millberry Scrap vs. Berry & Birch Copper: Complete ISRI Grade Comparison
Published on September 05, 2026 by MillberryCopper.com Trade Intelligence Desk
Key Takeaways & Summary
Learn the exact physical and chemical differences between ISRI Millberry (99.9%), Berry (96%), and Birch/Cliff (92-94%) copper scrap grades to maximize yard profits.
ISRI Grade Code Breakdown: Millberry vs. Berry
Under Institute of Scrap Recycling Industries (ISRI) circular standards, Millberry consists exclusively of clean, untinned, uncoated, unalloyed bare bright copper wire. Berry scrap, while also clean, includes wire with slight oxidation, hair wire under 16 gauge, or minor surface tarnish.
Wire Diameter and Purity Standards (>1.3mm / 16 Gauge)
To qualify as pure Millberry, wire thickness must equal or exceed 1.3mm (16 B&S gauge). Finer copper strands, telephone wires, or motor windings, even if bare bright, are classified as Berry or Birch due to higher melting oxidation rates in commercial crucible furnaces.
Chemical Analysis: Acceptable Oxidation & Moisture Limits
Spectrometric laboratory assays for Millberry require 99.90% minimum copper content, with lead, iron, tin, and zinc kept below 0.01% combined thresholds. Moisture, dirt, grease, or insulating varnish immediately downgrade the cargo to lower ISRI tiers.
How to Price Each Scrap Grade Against Spot LME Benchmarks
While Millberry commands LME minus 3% to 4%, Berry typically trades at LME minus 7% to 9%, and Birch/Cliff trades at LME minus 12% to 15%. Accurately sorting high-gauge cables before processing prevents significant revenue loss.
Trade Millberry Copper Scrap With Confidence
Connect directly with verified international scrap yards and refiners under Bank Letter of Credit (LC) and SGS assay inspection.