When I think of ISA candidates that should generate cash for decades to come, I think of companies like Aviva (LSE: AV). Life insurance is a pretty safe business, and Aviva has been providing a steady stream of dividend income for years. The company was hit in the financial crash and had to prune that dividend, but that’s only been for a few short years and this year’s payment should be back close to pre-crash levels.

Also, Aviva’s “transformation” plan of the past few years and its focus on strengthening the balance sheet and reducing risk has put it in a far healthier position to face the next decade — with full-year results for 2015, chief executive Mark Wilson told us that Aviva’s balance sheet is now “one of the strongest and most resilient in the UK“, adding that the firm’s economic capital surplus has tripled over the past four years.

With earnings per share set to resume growth, forecasts put the 473p shares on a P/E of a very modest 10, dropping as low as nine based on 2017 predictions. With well-covered dividends yields of 5% and 5.7% expected for this year and next, I’d certainly buy Aviva shares — oh, I did!

Good timing?

Picking the right shares is what ISA investing is all about, not worrying about the timing, but if you can get that too as a bonus then you can be off to a good headstart. A sector that might well be past its worst and on the way back up is the mining sector — and Antofagasta (LSE: ANTO) is one that could have a lot of potential. From a high in April 2015, Antofagasta shares crashed by 57% to a recent low on 20 January, but since then they’ve recovered 44% to reach 486p.

Why? Simply because the slump in commodity prices has started to reverse — in particular, the copper that the company digs up in South America has been recovering quite strongly since mid-January. Of course, metal prices could still falter and head down again, and the share prices of  mining companies would almost certainly go down with them. And with Antofagasta recovering from near-zero profit levels after a sharp dip in 2015, there aren’t any meaningful financial ratios to guide us.

But at results time chief executive Diego Hernández said that the firm’s actions over the past year means it “will be positioned to benefit from the recovery when it comes“. And it will come, and Antofagasta could be a nice long-term earner.

Fickle fortunes?

The fashion world is one I’m generally wary of as this year’s must-have can quickly turn into next year’s cast-off. But top-end fashion purveyor Burberry (LSE: BRBY) is a company that impresses me. The shares are down 30% since their February 2015 peak, which is in large part due to the slowing of Chinese growth and the spurning of luxury spend.

But Burberry shares have started to pick up again, putting in a 25% recovery since early January, and I can see them beating the market over the next year or two. For one thing, Burberry operates multi-nationally and is not dependent on one region, and its brand strength has helped it build an impressive moat around the business.

And demand in China, according to the firm’s Q3 update in January, has already started its return to growth. Long-term demand from developing markets is pretty much assured, I’d have thought, and I do see Burberry as a strong ISA candidate.

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Alan Oscroft owns shares in Aviva. The Motley Fool UK has recommended Burberry. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.