In the die-cast zinc alloy scrap business, many people just ask "how much per ton" right away. But for the same pile of material, some sellers get a higher price and some get lowballed. The difference usually comes down to not understanding the pricing logic. This article is for die-casters, recyclers, and traders. It explains the common sources of zinc alloy scrap, how aluminum and copper content affect price, and how scrap prices move with the zinc ingot market. After reading, you will understand where the discounts and impurity deductions on a quotation come from, and have more confidence when buying or selling.
1. Where does scrap come from?
Die-cast zinc alloy scrap mainly comes from three stages. 1. Die-casting production site: sprue, runner, and flash scrap. These have stable composition and few impurities, and are usually more valuable than scrapped parts. 2. Scrapped components: such as auto parts, locks, bathroom hardware, and power tool housings. If the surface has an electroplated layer or paint, watch out for copper, nickel, chromium and other impurities, which increase refining burden when reused. 3. Melting process by-products: zinc dross, zinc ash, and furnace bottom material. These are highly oxidized and fluctuate widely in zinc content, so the largest impurity deductions are applied during recycling. Also note that some materials look similar but come from different alloy series, such as high-aluminum zinc alloys or zinc-aluminum alloys. If mixed together, they contaminate each other. So before selling, you should sort clearly and store by source and appearance. Don't mix all zinc alloy scraps together. When recyclers see neatly sorted and clean material, they will quote more readily; a pile of mixed material is more likely to break the deal.
2. The impact of aluminum and copper
In die-cast zinc alloys, aluminum and copper are the core alloying elements. In common die-cast zinc alloy grades, aluminum content is roughly 3.9% to 4.3%. Copper content depends on the grade; for example, the so-called No. 3 zinc alloy has essentially no copper, while No. 5 zinc alloy contains about 1% copper. Aluminum improves fluidity and strength, but if aluminum in scrap is significantly excessive, surface dross increases obviously during melting. That dross carries away metallic zinc and lowers the actual yield. In addition, high aluminum shifts the solidification temperature, which has adverse effects on subsequent reuse in casting. Copper increases hardness and wear resistance, but if copper is too high, the alloy becomes hard and brittle, making processing more difficult. If a batch of scrap has high-copper bronze parts or copper-plated parts mixed in, the recycler must do extra processing. Conversely, scrap whose composition falls within the standard range can be directly charged into production, reducing the cost of adding alloying elements, so the price naturally has support. In terms of handling, recyclers usually use a spectrometer to quickly get an elemental spectrum. Quotes without assay are subjective guesses. To avoid being lowballed, a seller should proactively provide an assay report or allow on-site sampling – that is a better strategy.
3. Linkage with zinc ingot market
The pricing of zinc alloy scrap is essentially a discounted price based on the zinc ingot spot price. Scrap cannot be sold directly as zinc ingot; it must go through sorting, melting, refining, and composition adjustment before being cast into alloy ingot or zinc ingot. This process involves melting loss, dross, and energy consumption, and recyclers also bear financing costs. Therefore, the scrap price quoted by recyclers is always lower than the zinc ingot spot price on the same day. The linkage between the two is simple – when zinc ingot rises, scrap quotes rise; when zinc ingot falls, scrap quotes also drop. But the magnitude is not necessarily synchronized: when zinc ingot surges, scrap quotes often rise half a beat slower, because recyclers worry about a pullback from high levels; when zinc ingot plunges, scrap quotes may fall even harder, because buyers have a strong tendency to push prices down. Some recyclers adjust their quotes every day based on the prices on the Guilin Nonferrous Metals Network. This habit is worth copying. As a seller, get quotes from at least three recyclers before shipping. Besides comparing the unit prices they quote verbally, also ask clearly: "What is the base price? What is the discount? How much is deducted for impurities?" Different recyclers can have quite different assessments of the same batch of material.
4. Pricing formula and impurity deductions
In actual trading, pricing zinc alloy scrap is not as simple as multiplying by a coefficient. The common process has several steps. Step 1: weigh to get gross weight, then deduct moisture, sand, iron pieces, plastic seals and other entrained materials to get net material weight. Step 2: take a sample for assay to determine the actual zinc content and the percentages of elements such as aluminum, copper, iron, and cadmium. Step 3: estimate the melting recovery rate based on the material type. Clean, thick sprue can be judged at over ninety percent, while fine chips and oxidized powder are often only seventy or eighty percent or even lower. Step 4: using the day's zinc ingot spot price as a benchmark, multiply by the estimated recovery rate, then subtract the melting processing fee, freight, and the recycler's profit, to get the final unit price. Some recyclers directly quote a "package price", i.e., a flat price, but if it is not clearly written out how much was deducted for impurities and what zinc content was assumed, disputes are easy to arise. It is suggested that sellers do their own calculation first: gross weight, moisture content, zinc content, recovery rate. Then work backward from the other party's quote to see whether the deductions are reasonable.
5. Risk control in buying and selling
In zinc alloy scrap transactions, the risk is not the material itself, but market fluctuations. Buyers are afraid that after taking delivery, zinc prices will fall; sellers are afraid that after selling, zinc prices will rise. To control this risk, don't leave prices in the vague zone of a "verbal agreement". For large-volume transactions, it is recommended to state explicitly in the contract: use the spot price of zinc ingot on a specific date as the pricing benchmark, and list clearly the specifications, quantity, delivery date, impurity deduction standard, and settlement method. If the delivery period exceeds one week, you can also agree on a price adjustment clause – for example, if the zinc ingot price fluctuates by more than a certain percentage, the two parties will renegotiate the settlement price. For small transactions, also note on the delivery note the "pricing benchmark date" and the "moisture/impurity deduction ratio". In addition, if iron blocks, screws, or sealing rings are mixed into the scrap, it not only affects the impurity deduction negotiation, but may also damage the furnace lining during melting. Such materials will be rejected by recyclers or dramatically discounted. Finally, don't treat scrap pricing as pure guts. Ask around about the processing radius and freight costs of peers. Only after factoring in costs should you quote, so you won't suffer hidden losses.
Common Questions
Q: Does zinc alloy scrap price follow the zinc ingot price?
Yes. Scrap quotes are basically discounted from the zinc ingot spot price. When zinc ingot rises, scrap rises with it, but the magnitude and pace may differ. For real-time market prices, check the market page on the Guilin Nonferrous Metals Network. When negotiating, convert directly based on the day's benchmark price. Don't use outdated prices.
Q: Why does high aluminum content lower the scrap price?
When aluminum exceeds the standard range, it increases dross during melting, reduces the metal recovery rate, and requires composition adjustment, all of which raise recycling costs, so the unit price is pushed down. Conversely, when composition is close to common grades, recycling is easier and the price can be higher.
Q: Is copper content beneficial to pricing?
Within the standard range (for example, about 1% copper in No. 5 zinc alloy), copper improves hardness and wear resistance, which is beneficial for recycling and reuse. But too much copper makes the alloy hard and brittle, requiring downgrading or dilution, which actually lowers the price. The key is whether the total content matches the target grade.
Q: How do you judge what grade the scrap is roughly?
A rough look at the fracture surface and toughness can only give a guess. For accuracy, run a spectrometer test or wet chemical analysis. During a transaction, it is best to have the recycler test on site with a spectrometer, print out an element content report, and rely on data to avoid grade disputes.
Q: Can zinc dross and zinc ash be sold at scrap prices?
No. They cannot be sold at normal scrap prices. Zinc dross and ash are heavily oxidized, and the metallic zinc recovery rate is low. They can only be quoted based on the calculated zinc content, usually far below clean lump material. Removing iron and sand before selling can improve the recovery rate a little.
Q: Why do recyclers deduct moisture and inclusions?
Moisture consumes energy during melting, and inclusions do not produce metallic zinc but add to the slag. Therefore, they must be deducted from the gross weight at weighing. This is not deliberately cheating on the scale, but a common industry conversion practice. Reasonable impurity deductions should specify the standard clearly.
Q: How do small-batch deliveries avoid being ripped off?
First ask clearly which date's zinc ingot price is the pricing benchmark, and what the moisture and impurity deduction standards are. Keep the weighbridge ticket, retain samples, and keep the assay report stamped by the other party. Don't just compare the "flat price". Break it down and look at the base price, zinc content, and recovery rate.
Q: When zinc prices fall, should I sell or hold scrap?
If your cash flow is not tight and your usage is small, you can wait for the market to recover. But you need to calculate inventory holding costs and the risk of further price declines. Ordinary owners should not bet on a one-way market. Ship in batches by proportion, which smooths out risk and retains the possibility of a price rise.
Key Takeaways
1. Scrap price = zinc ingot spot price × comprehensive coefficient. The coefficient is determined by material type, zinc content, and impurities. 2. Sprue and large clean lumps get small discounts; zinc ash and zinc dross get large discounts. Sort first, then negotiate. 3. Try to keep aluminum and copper contents close to standard grades. Let the assay report speak before the transaction. 4. Deducting moisture, impurities, and processing fees is an industry rule. Learn to work backward through the pricing process. 5. For large-volume transactions, agree on the pricing benchmark date and contract terms to avoid disputes over market fluctuations.
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.*