I love buying cheap FTSE 100 dividend shares with high yields, and these two have caught my eye. Both offer a mighty income stream at a decent price. What’s going on?

The first is mining giant Rio Tinto (LSE: RIO). Its shares have a price-to-earnings ratio of exactly nine, comfortably below the FTSE 100 average of 15.4 times. The trailing yield is a bumper 6.7%, more than double the blue-chip average of 3.5%. The fact that it’s covered 1.7 times by earnings suggests it’s sustainable too.

This combination of a high P/E and high yield often indicates a falling share price, and that’s the case here. The Rio Tinto share price has slumped 5.76% over 12 months, badly trailing the FTSE 100 as a whole, which grew 10.33%.

Like every mining stock, Rio Tinto been hit by falling Chinese demand for metals and minerals, as the world’s second-biggest economy slows.

I’d love to buy today

Despite that, Rio still posted underlying first-half earnings of $12.1bn on 31 July, generating $7.1bn of net cash from operating activities. “Rio Tinto is both consistently very profitable and growing”, according to CEO Jakob Stausholm. Investors are sharing in its success, as the group paid an interim ordinary dividend of $2.9bn, meeting its target of paying out 50% of underlying earnings.

The dividend looks solid to me but why so cheap? Investors are waiting to see if Beijing can revive Chinese growth, but recent stimulus packages have fallen short. And while investors are rooting for a US soft landing, the country’s massive deficit and debt are quietly rolling up.

Yet I think Rio Tinto looks a solid long-term buy for dividend income and share price growth. I’d like to snap it up before stock rises, rather than afterwards, so will do as soon as I have the cash.

My second high-yield, low-valuation stock is cigarette maker Imperial Brands (LSE: IMB). Personally, I don’t buy tobacco stocks, but I do like to check them out from time to time, if only to see what I’m missing.

I wish I could buy Imperial Brands

Today, I’m sacrificing a juicy 6.5% yield available at a cut-price P/E of 8.46 times. And that hurts.

Imperial Brands continues to throwing money at loyal investors, targeting £2.8bn of dividends and share buybacks this year, up from £2.4bn in the last one.

Tobacco stocks are traditionally cheap as investors accept that government health and regulatory campaigns will slowly squeeze sales, especially in the developed world, leaving manufacturers scrapping over their share of a dwindling market.

Now here’s the shock twist. The Imperial Brands share price has rocketed 30.87% over the past 12 months. Over three years, it’s up a stunning 50.73%, smashing the index. I knew I was missing out on bags of income here, but didn’t realise I was sacrificing a heap of growth too.

While smoking will decline, vaping is helping to plug the gap. This source of revenue can’t be relied on though, as regulators fight back. So there are still risks and recent breakneck share price growth must surely slow at some point.

That said, if I bought tobacco stocks, I’d buy Imperial Brands like a shot. Missing out on this opportunity is enough to make me take up smoking! This could be one for investors to consider.