As with all investments there is no guarantee on returns, even with crypto investing.
This however the guarantee is that you own actual shares in the company and you will receive dividends (manufacturing co.).
When listed you will have liquid shares, which you can sell on the market and cash out at a higher price.
The time frame for the mining company is of course a bit more longer, though to listing is within 6 months, but to realise a big appreciation in price per share might take about 1yr or so.