Tolling

Tolling is the process by which a material containing metal (one or more valuable analytes) is processed (for example, in a refinery) by one organisation on behalf of another organisation. The metal contained in the material is and remains the property of the owner organisation. The organisation doing the processing is compensated by contractually defined tolling fees, such as treatment charges and refining charges.

Tolled materials are:

  • Physically returned to the owner organisation or an agreed third party, either in the form of refined metal or a semi-refined material
  • Priced and purchased by the organisation doing the processing

In some cases, a purchase contract for a material may also contain tolled analytes.

If an analyte is to be tolled, the applicable tolling account must be specified for that analyte in the sales or purchase contract.

Toll Account Transactions

Toll account transactions are created:

  • When a despatch order with tolled analytes has a bill of lading date and the despatch order assay values snapshot is calculated by the MineMarket Marketing Service
  • When direct loading or unloading transactions are saved for the toll account

The transaction date for material that is added to or taken from a toll account is the same as the bill of lading date.

For material that is added to a toll account, there is also an availability date. This is the date that material becomes available for out-going transactions. How the availability date will be calculated is specified for each tolled analyte, and can be a fixed date, a calculated date, or a date based on predefined functions such as MOS or MAMA.

In order to create direct loading or unloading transactions for a toll account, an applicable process flow must be created that specifies the toll account's location as a source or destination location for the process flow.

However, a toll return transaction is simpler to configure than a direct loading or unloading transaction. Fixed quantity toll returns can also be used to transfer material between toll accounts.

When tolled material is to be returned to the customer with a zero value on the invoice for that analyte's line item, this can be set up as a full toll return or a fixed value toll return.

Tolled material can also be purchased with toll pricing. In this case, pricing information (a QP) must be specified for the analyte or product in the contract or overridden in the despatch order.

Calculation of the Accountable Metal Quantity

The amount of material in the tolling transaction is calculated with the following process:

  1. Determine the applicable assay values:
    1. If assays are final, use the final values.
    2. If assays have been exchanged, but not finalised, use the specified pre-settlement method.
    3. If assays have not been exchanged, use assay factoring.
  2. Apply any specified mass adjustment.
  3. Determine the payable assay (PA) by applying payable content and minimum deduction rules.
  4. Determine the applicable weight (W) by considering any deduction or weight allowance.
  5. Calculate the payable content (PC) as:
    PC = PA * W
  6. If the assay exchange for the analyte is incomplete, multiply the PC by the non-final tollable percentage.

If values change, the tolling transaction quantity is recalculated.