Antimony at Camel Creek - What Happened?, page-15

From Chat GPT thought us punters should have something to consider as its so dead in here!

Step-by-Step Breakdown

1. Assumptions for Gold and Antimony Prices

• Gold Price: $2,300 USD/oz (current average as of May 2025)

• Antimony Price: $13,000 USD/tonne (approximate average)

2. Gross In-Situ Value (Before Costs)

• Gold:
  202,000 oz × $2,300/oz = $464.6 million

• Antimony:
  9,000 t × $13,000/t = $117 million

Total In-Situ Value = $581.6 million

3. Recovery Rates

• Gold Recovery: ~90% (heap leach/CIL – typical for open pit)

• Antimony Recovery: ~75% (variable depending on processing)

• Recovered Gold Value: $464.6M × 90% = $418.1 million

• Recovered Antimony Value: $117M × 75% = $87.75 million

Total Recoverable Value = $505.85 million

4. Operating Costs

Typical all-in sustaining cost (AISC) assumptions:

	Cost Component	Value (USD)
1	Gold AISC	~$1,200/oz × 202,000 oz = $242.4M
2	Antimony Opex	~$7,000/t × 9,000 t = $63M
3	Total Costs	$305.4 million

5. Capital Expenditure (CAPEX)

Initial infrastructure, processing, permitting, etc.:

• CAPEX Estimate: ~$80 million (based on small-scale operation, open-pit, combined Au-Sb plant)

6. NPV Calculation

We'll calculate NPV at a discount rate of 8%, over a 10-year LOM (life of mine) production schedule. For simplification, we'll treat cash flows as even.

Estimated Annual Net Cash Flow:

• Net Revenue = $505.85M – $305.4M = $200.45M

• Assuming 10-year mine life:
  Annual Net Cash Flow ≈ $20.05M/year

Now discounting over 10 years:

NPV=∑t=11020.05M(1+0.08)t−80MNPV = \sum_{t=1}^{10} \frac{20.05M}{(1 + 0.08)^t} - 80MNPV=t=1∑10(1+0.08)t20.05M−80M

This results in:

• NPV ≈ $67 million