How do you value a metal streaming deal?

Value a stream as a margin instrument: margin per ounce equals the metal price minus the contractual delivery price minus allocated corporate overhead. Multiply that margin by the annual gold-equivalent ounces the stream delivers, deduct tax, and discount the resulting cash flows over the stream's life. The valuation turns on three contract terms: the delivery price (fixed dollar or percentage of spot), the percentage of production delivered, and any step-down clauses that cut deliveries after a cumulative threshold.

What is a typical stream delivery price as a percentage of spot?

Newer streaming deals set the ongoing delivery price at 15-25% of the spot price. Verified recent examples: Wheaton's Kurmuk gold stream at 15% of spot (December 2024), Franco-Nevada's Casa Berardi stream at 20% of spot (January 2026), and Wheaton's Antamina silver stream at 20% of spot silver (completed April 2026). Older contracts often fixed the delivery price in dollar terms instead, which gives the streamer more leverage to rising metal prices.

What is the difference between fixed-dollar and percentage-of-spot delivery pricing?

A fixed-dollar delivery price stays constant whatever the metal does, so the streamer's margin captures every dollar of price upside and its margin percentage expands as spot rises. A percentage-of-spot delivery price scales with the metal, so the margin percentage stays constant (an 80% gross margin at a 20% delivery price, at any gold price). Fixed-dollar contracts are the older structure; most deals signed since the mid-2010s use percentage of spot because operators refused to keep writing one-way bets on the metal price.

What is a stream step-down clause?

A step-down clause cuts the percentage of production the streamer receives once cumulative deliveries hit a contractual threshold. The live filed example is Triple Flag's Cerro Lindo silver stream, which steps from 65% of payable silver down to 25% once cumulative deliveries pass 19.5 million ounces. Triple Flag had delivered 18.9 million ounces by the end of 2025, and the reduced rate applied from April 2026. Step-downs compress later-year cash flow even if the mine keeps producing at the same rate, so a stream model must follow the contract schedule, not a flat delivery assumption.

How to Value a Metal Stream: Margin per Ounce

Educational analysis for professional use. This guide is not investment advice or a recommendation to buy or sell any security, and it is not personalised.

A Stream Is a Margin Instrument

A metal stream is worth the margin it earns on every ounce, multiplied by the ounces it delivers, discounted over the life of the contract. That is the whole model. The streamer paid its capital upfront; what remains is a long-dated spread between the metal price and a contractual delivery price, less a thin layer of corporate overhead.

So stream valuation comes down to three contract terms:

The delivery price: what the streamer pays the operator per ounce, either a fixed dollar amount or a percentage of spot.
The stream percentage: what share of the mine’s production the streamer is entitled to buy.
Step-down clauses: thresholds after which that share drops.

Set all three correctly and the rest is discounting. Botch any one and the answer is wrong by more than the gold price assumption would move it.

Fixed-Dollar vs Percentage-of-Spot Delivery Pricing

The delivery price structure decides who owns the metal price upside. A fixed-dollar price hands it all to the streamer; a percentage-of-spot price splits it in a constant ratio.

Feature	Fixed-dollar delivery	Percentage-of-spot delivery
Delivery cost	Set in the contract, in dollars per ounce	Scales with the metal price
Margin as spot rises	Expands dollar for dollar; margin % rises	Grows in dollars; margin % constant
Margin as spot falls	Compresses fast; can go negative in theory	Compresses proportionally; margin % held
Who bears price risk	Operator sold the upside	Shared in fixed proportion
Where you see it	Older contracts	Most deals since the mid-2010s

Fixed-dollar pricing made streamers spectacular bull-market vehicles: every dollar on the gold price fell straight to margin. Operators noticed, and the structure migrated. Newer deals run at 15-25% of spot, and the recent filed terms cluster tightly:

Deal	Streamer	Delivery price	Source date
Kurmuk gold stream	Wheaton	15% of spot	December 2024
Casa Berardi stream	Franco-Nevada	20% of spot	January 2026
Antamina silver stream	Wheaton	20% of spot silver	Completed 1 April 2026

When you model a stream, read the delivery mechanism out of the filing. Assuming percentage-of-spot on a fixed-dollar legacy contract (or the reverse) misprices the asset’s entire sensitivity to the metal.

The Margin-per-GEO Build

Margin per gold-equivalent ounce is a three-line subtraction: spot price, less delivery price, less corporate overhead allocated per ounce. Everything else in the stream model hangs off this number. (If the GEO normalisation itself is unfamiliar, start with what a gold-equivalent ounce actually measures.)

Margin per GEO = metal price − delivery price − overhead per GEO

We build on a long-term planning price of $3,500/oz rather than a spot print, which keeps NAV honest. At a 20% delivery price and $30/GEO overhead:

$3,500 − $700 − $30 = $2,770 per GEO

Sweep the delivery price from 18% to 20% and the overhead from $30 to $50 per ounce, and the margin lands at roughly $2,750-2,840/GEO. The full delivery-price sweep at $30/GEO overhead:

Delivery price (% of spot)	Delivery cost per GEO	Margin per GEO	Margin %
15% (Kurmuk)	$525	$2,945	84%
18%	$630	$2,840	81%
20% (Casa Berardi, Antamina)	$700	$2,770	79%
25%	$875	$2,595	74%

The real-world check: Wheaton reported a FY2025 cash operating margin of $3,040/GEO against a realised price of $3,554/GEO, a cash margin of about 85.5% before overhead. That is how the largest streamer’s income statement actually behaves.

From margin to value, three more steps. Multiply margin per GEO by the annual ounces the stream delivers, apply tax (assume a flat 15% rate here; streaming tax structures are their own trap and can swing NAV 20-30%), then discount over the contract life. Whether the resulting price paid per ounce of annual delivery was a good deal is a separate question, answered by the $/GEO accretion test.

Why the Delivery Percentage Matters More Than It Looks

A five-point shift in the delivery percentage looks trivial next to the gold price assumption. It is not. Move the delivery price from 20% to 25% of spot and the margin per GEO drops from $2,770 to $2,595. That is about 6% off every ounce, for the life of the contract, from a term buried in a schedule.

Run the same logic in reverse and you see why streamers fight for every point at the negotiating table. Kurmuk’s 15% terms against a generic 25% deal is a margin gap of $350/GEO at planning gold, on every ounce, for the life of the contract. Two streams on identical mines with identical upfront payments can differ in value by more than 10% purely on the delivery clause.

The practical rule: never default the delivery percentage. Pull it from the contract, and sensitise NAV across at least a five-point range before trusting the output.

Step-Down Clauses: The Later-Year Compression

Many stream contracts cut the streamer’s share of production once cumulative deliveries reach a threshold. The mine keeps producing; the streamer’s ounces fall away. A model that runs a flat delivery assumption across the full mine life overstates every year after the step-down.

Triple Flag’s Cerro Lindo silver stream steps from 65% of payable silver down to 25% once cumulative deliveries pass the contract’s 19.5 million ounce threshold. Triple Flag had delivered 18.9 million ounces at the end of 2025, and the reduced rate began with April 2026 deliveries. Cerro Lindo was 23.1% of Triple Flag’s FY2025 gold-equivalent ounces, its second-largest asset, so the step-down materially reshapes the company’s delivery profile from here.

Step-downs change three things in how you model:

A stream with a step-down earns most of its NPV before the threshold; check what share of your modelled value sits in the pre-step years. Discounting punishes the thin tail.
The trigger is cumulative ounces delivered, not a calendar date. Tie the threshold year to your production schedule: faster mining pulls the step-down forward, a slow ramp defers it.
Disclosed “stream percentage” figures often describe the current entitlement. The filing’s step schedule is what the model needs, not the headline.

Common Mistakes in Stream Models

Valuing on spot. Build the base case on a long-term planning price, not today’s market print. A NAV built at an elevated gold cycle is one mean-reversion away from embarrassment.
Wrong delivery mechanism. Fixed-dollar and percentage-of-spot streams respond completely differently to a metal price move. Confirm which one the contract specifies before sensitising anything.
Defaulting the delivery percentage. A 20%-to-25% slip costs about 6% of margin on every ounce. Five points is not a rounding choice.
Ignoring step-downs. Flat delivery assumptions overstate later years. Cerro Lindo’s 65%-to-25% step is a live example.
Forgetting overhead and tax. $30-50/GEO of corporate overhead and the effective tax rate both belong in the margin build. Gross spread is not cash flow.

Where This Fits

Margin per ounce is the unit economics of the entire streaming model; portfolio NAV is just this calculation repeated across every contract and summed. The Royalty & Streaming Sector Primer builds that full sum-of-parts framework, including the discount-rate tiers, the risking of development-stage streams, and the deal-evaluation toolkit that prices a new stream against the buyer’s own multiple.