Tin price, page-96

Regarding the expense the mine dev costs for tax purposes, this is more complicated to work out, but if you look at the tax at Note 8 of the financials, you can see MLX has a deferred tax liability of $9m for the mine dev (see screenshot below).

This means, they've historically written off the mine dev costs for tax purposes in the year they incurred the expenses rather than capitalising it and then depreciating/amortising it over the LOM. Why it is classified a tax "liability" not an "asset" is purely a semantic construct of accounting but if you wish to understand, the very brief explanation is that future amortisation of the mine dev costs in the PnL are not tax deductible (because they've already taken the upfront 100% deduction so no double dipping). That's why it is a liability.

Now, these differences between tax and accounting will wash out over the LOM such that the differences are merely timing.

Regarding the tax losses that @@Cashmeoutside and other posters have been discussing, MLX have $254.5m of "tax losses" theoretically available for them to use to offset future taxes. This number is the amount of tax , so the tax-free before-tax profit figure is actually $846.7m.

However, there is one big qualification to the $846.7m figure:

$521m is subject to a restricted rate of utilisation ($156.3 divided by 30%). There is an special tax rule called "available fraction" which no one here needs to understand, but it basically means there is a question mark about how much of the $521m is available for MLX to use each year.

Therefore, the actual amount of tax free before-tax profit that MLX can generate is closer to $325m.

Now there will be some differences between accounting profit and taxable profit, depending on the rate the deferred tax/liability timing differences unwind each year, but $325m tax free profit is nothing to sneeze at.