Why is zinc payable lower (~85%) than copper payable (~96%)?

Zinc smelting is energy- and process-intensive per MT of contained metal. The smelter retains 15%+ of the contained zinc as its processing margin. Copper smelting has higher recoveries, so payable is closer to 97%.

How are Hindustan Zinc's sales contracts structured?

Typically 'LME Zinc Cash × payable %' with TC deducted separately. The catalog's assay × payable derivation models this exactly; TC settlement is commercial.

Can I override payable % per contract?

Yes. Each concentrate shipment (especially long-term offtake agreements) can override the typical 85% at position entry without changing the catalog default.

Does lead concentrate or bulk Pb-Zn concentrate use this product?

No. Lead or bulk Pb-Zn concentrate needs its own product entry with separate assay/payable for each metal. The catalog is zinc-only here.

Worked exampleZincConcentrateConcentrate

Zinc concentrate

Name: Zinc concentrate
Brand: Novaex
SKU: zinc-concentrate

Standard zinc concentrate (48–56% Zn)

Zinc concentrate flows from mines (Hindustan Zinc, Vedanta Zinc International, Glencore) to smelters worldwide. Assay × payable captures the two deductions. Physical grade and smelter share. That spreadsheet hedging routinely gets wrong.

This page shows how the NovaEx wizard models one common configuration. Your contract may look different. Override any field per shipment, or clone the example to build your own.

Last updated: April 2026By NovaEx Product

Conversion recipe

DMT × A% × P%

Hedge methodAssay × payable %

FormulaHedgeable MT = DMT × Assay % × Payable %

Commercial UOMDMT

Assay48–56% (typical 52%)

Payable80–90% (typical 85%)

Moisture (Wet MT)8–12% (typical 10%)

Rounding ruledown

Sources

International Lead and Zinc Study Group · International Zinc Association · Hindustan Zinc annual reports

Industry-standard ranges shown. Actual contract terms vary per shipment; override at position entry.

Worked example

Typical shipment

Commercial qty

25 DMT

As invoiced

Contained metal

13.00 MT

Zinc inside the goods

Hedgeable metal

11.05 MT

Flows to hedge desk → LME Zinc

Contained = 25 DMT × 52% assay = 13.00 MT. Hedgeable = 13.00 × 85% payable = 11.05 MT Zinc hedgeable.

25 DMT × 52% assay × 85% payable = 11.05 MT Zn hedgeable → hedge on LME Zinc.

Typical specifications

What you're actually trading

Reference specifications for contracts, counterparty conversations, and supply-chain planning. Not a substitute for the shipment's lab certificate or commercial contract.

Assay: 48–56% Zn (typical 52%)
Payable: 80–90% (typical 85%)
Moisture (Wet MT): 8–12% (typical 10%)
Commercial UOM: DMT (dry) or Wet MT
Indian context: Hindustan Zinc Ltd is the dominant domestic concentrate producer