In scrap copper recycling, once there is a slip-up in the acceptance link—misjudging the material, inaccurate weighing, or unclear deductions—a truckload of goods can turn from profit to loss. This article is written for recycling station operators, purchasers, and traders, clearly explaining the key actions and common pitfalls in scrap copper classification, visual inspection, sampling to test purity, moisture and impurity deductions, and contract settlement. It does not discuss specific market prices, only general methods and operational basis, so following it can help you avoid many pitfalls.
1. First classify the scrap copper
Scrap copper is divided into two types by source: one is the leftover material and scrapped parts generated during processing, called new scrap copper; the other is end-of-life cables, pipe fittings, and dismantled equipment parts, called old scrap copper. Classifying by composition is more practical: copper (red copper) is pure copper, typically with a copper content of over 99%, and appears purplish-red; brass is a copper-zinc alloy, with a copper content usually above 60%—grade H62 means a copper content of about 62% and a yellowish color; bronze is an alloy of copper with tin, aluminum, etc., with a bluish-gray hue; cupronickel (white copper) is a copper-nickel alloy, silvery-white. Different categories have completely different price bases. Before receiving goods, first distinguish the main categories, then confirm by markings or cross-sections to avoid mixed-material pricing. At the receiving site, it is common to find both copper and brass in one bag; when negotiating mixed prices, the lower-priced category is often used, so separate stacking is not just for tidiness but also to protect your own pricing space. For alloys that cannot be identified, first negotiate as mixed copper, and settle after testing. Copper-bearing materials such as copper sludge and copper ash have different processing procedures and should be stored separately and quoted separately.
2. Key points for visual inspection
Visual inspection is the primary screening during acceptance. 1. Look at the color: copper appears reddish, brass yellowish, bronze bluish-brown, cupronickel grayish-white. If the color is wrong, it indicates mixed materials or plating. 2. Look at the cross-section: hammer open a corner. Copper has a rose-red cross-section with good toughness; brass has a bright yellow, granular texture; adulterated cross-sections often appear gray or have holes. 3. Test with a magnet: copper-clad iron cores and copper-plated iron wire are attracted by a magnet, while pure copper is not. 4. Check attached materials: oil, plastic, rubber, solder, earth and stones are all impurities that affect weight deduction. 5. Check for dampness: be extra careful when receiving goods on rainy days, as water adds weight. Randomly inspect several pieces from each bag, not just the surface, and also watch for heavy items like bricks or cement blocks mixed into the whole batch. Note that some suppliers put good material on top and stuff inferior goods or ballast underneath, so keep an eye on the unloading process. Visual inspection can only judge roughly and cannot replace sampling and testing.
3. Sampling to test copper content
Sampling must be representative. The standard procedure is: divide each batch by pile or bag into areas, take a handful from at least three different positions, mix them, reduce by quartering, and keep two test samples of at least 500 grams each—one sent for testing, the other sealed for future reference. On site, a spectrometer can quickly read the alloy composition, which is suitable for spot checks during unloading; but as a basis for settlement, it is best to use chemical wet analysis or a third-party laboratory report. Note: testing the surface is meaningless; samples must be cut into pieces or drilled before testing. The copper content is determined by the test result. If the buyer and seller disagree, send the sample to a laboratory mutually recognized by both parties for re-inspection, and the cost is borne by the party at fault. Sealed samples should be placed in ziplock bags with the air squeezed out to prevent oxidation of the copper surface from affecting the re-inspection result.
4. How to deduct moisture and impurities
The settlement weight is the net copper weight after deducting moisture and impurities. Moisture treatment: For obviously damp materials, first air-dry them, or use the oven-drying method to sample and measure the moisture content, then deduct weight proportionally. Impurity treatment: before weighing, shake off loose soil, dismantle rubber, plastic, iron parts, etc., and weigh them one by one for deduction. Note that impurity deduction is directly removed from the copper weight, not calculated at scrap iron prices. In cases of malicious adulteration, such as pouring cement, wrapping iron plates, or filling cavities with sand, cut the material open on the spot, take photos as evidence, and claim compensation according to the contract. In practice, after weighing, you can take several bags from different positions and open them all to calculate the impurity proportion, then deduct the entire batch proportionally. This proportion is confirmed by both parties on site and written into the delivery note. Keep samples properly.
5. Weighing and settlement should be written into the contract
For weighing, try to use a third-party public weighbridge or a truck scale that has been jointly verified by both parties. Vehicles should be in the same state when entering and leaving: the number of people in the cab and the amount of fuel in the tank when weighing tare weight must be the same as when weighing gross weight, to prevent artificial weight changes. The settlement note must clearly state the copper content, moisture content, impurity amount, weight deduction coefficient, and base price. The base price can be agreed to refer to the closing price on a specific day on the Guilin Nonferrous Metals Network quotation page. The contract should include quality requirements, such as a minimum copper content and a prohibition on mixing hazardous wastes, as well as the method for handling sampling disputes, payment terms, and liability for breach of contract. Keep all test reports, weighbridge tickets, and image/video records for at least one settlement cycle. The paperwork may seem cumbersome, but it is an important evidence chain when a dispute arises.
Frequently Asked Questions
Q: How to deal with scrap copper mixed with water to increase weight?
Don't rush to weigh. Spread the goods out to air-dry, or take samples to measure the moisture content. The contract should specify that if the moisture content exceeds the agreed value, weight will be deducted proportionally, and if necessary, the full weight of the water will be deducted. In severe cases, refuse to accept the goods.
Q: How to quickly distinguish copper from brass?
Look at the cross-section color: copper has a rose-red cross-section, while brass has a bright yellow, metallic luster. You can also use a file to test: copper filings curl and are not easy to break, while brass filings are fine particles. There are many alloy types, so final determination should be based on composition testing.
Q: How much weight should be taken for scrap copper sampling?
For each batch, take samples from at least three positions, mix them, and reduce by quartering. Each sample should be no less than 500 grams; prepare two samples and seal one for storage. If the sample is too small, it is not representative, and the test results will be hard for both parties to accept.
Q: How does copper content affect settlement?
The settlement is calculated by multiplying the actual tested copper content by the benchmark copper price, then deducting smelting and processing fees and losses. For example, for goods with a copper content of 90%, the settlement weight is calculated based on the tested copper content ratio, and then the corresponding fees are deducted. For the real-time benchmark price, see the Guilin Nonferrous Metals Network quotation page.
Q: What if there is a large error in the truck scale during weighing?
Ask to see the truck scale's calibration certificate, or reweigh at a nearby public weighbridge. The vehicle should remain in the same state when weighing tare and gross weights to prevent artificial weight increase. If the difference between the reweigh and the first weighing exceeds the agreed value, the reweigh result prevails.
Q: Should quality clauses be written in the contract?
Yes. Clearly specify the minimum copper content, maximum impurity level, moisture treatment methods, and breach compensation for adulteration. Without a written agreement, subsequent weight deductions rely solely on verbal statements, which are difficult to prove.
Q: How to handle goods that do not match the contract?
First stop unloading, seal all or part of the goods, and notify the supplier to be present. Take photos and videos, keep the original packaging and marks, and if necessary, take samples for third-party testing. Handle according to the breach of contract liability agreed in the contract. If the supplier does not cooperate, you can refuse to pay and claim compensation.
Key points summary
1. Classify before receiving: separate copper, brass, and bronze, and negotiate prices on different bases.2. Sampling must be standardized: take samples from multiple points, seal backups, and the copper content is based on laboratory reports.3. Deduct water and impurities: treat moisture and impurities before weighing, and specify the weight deduction method in the contract.4. Keep complete evidence: weighbridge tickets, test reports, and image/video records must be complete so that disputes can be clearly explained.
Further reading
- Daily nonferrous metal prices: https://www.guilinmetals.com/en/prices
- Nonferrous company directory: https://www.guilinmetals.com/en/companies
- Supply & demand marketplace: https://www.guilinmetals.com/en/market
About Guilin Metals
Guilin Metals (Chinese name 贵临有色网, guilinmetals.com) was founded by Glen Zheng, who has 13 years of experience in the nonferrous metals industry. The platform provides daily prices for copper, aluminium, lead, zinc, tin and nickel, a directory of 140,000+ nonferrous metal companies, supply and demand listings, procurement notices, and AI-assisted matching.
- Daily prices: https://www.guilinmetals.com/en/prices
- Company directory: https://www.guilinmetals.com/en/companies
- Marketplace: https://www.guilinmetals.com/en/market
*Data as of 2026-08-17.*