In these days of near-historic low interest rates, it can be hard to find an investment that yields more than a cupful of spare change. This is true for stock dividends; in fact, the average of dividend-paying stocks on the S&P 500 index was a mere 1.9% at the time of this writing.

There are much richer payouts to be had if you know where to look, though. For proof, take a gander at these three high-yield dividend stocks.

Three rolls of $100 bills

Image source: Getty Images.

Iron Mountain

One of the most valuable assets in today's economy is data. Iron Mountain (NYSE:IRM) is a company that specializes in storing and securing it and other forms of information in both digital and hard-copy form. It operates more than 1,400 facilities around the world, which all told cover 85 million square feet of space. .

The company, structured as a real estate investment trust (REIT) these days, is a longtime player in secure records management -- so much so that some estimates have its market share at nearly 100%. It has roughly 225,000 organizational customers, and its corporate clients represent a wide variety of business sectors (meaning it isn't beholden to any one or any group).

From an income investor standpoint, the great advantage of owning a REIT is that it is obligated by law to pay out the great bulk of its profits as shareholder dividends. Happily, Iron Mountain has generally managed to lift its net profit over the years, so there's more dosh to be shared with stockholders.

Iron Mountain's dividend is doled out quarterly, and currently stands at $0.61 per share. At the most recent closing share price, this high-yield stock garners nearly 6.9% on its share price.

Blackstone Group

Blackstone Group (NYSE:BX) is a sprawling financial industry company active in segments that aren't necessarily compatible: Its main activities cover private equity, real estate, and credit. It's more of an opportunistic player, a sharp-eyed operator always on the prowl for a good investment. Over the years, it's done a fine job of accumulating productive assets to bulk up to its present size.

If you think the mentioned segments can (and probably will) be rather volatile, you're right. Blackstone's revenue and profitability tend to wave around quite a bit. Fortunately, since the company has a knack for finding very productive assets, it typically manages to book net profits at high margins (24% in fiscal 2018, for instance).

So there's basically always a dividend, although the exact amount can be hard to predict from quarter to quarter. Still, Blackstone's high profitability and high payout ratio practically ensure that it will be generous.

Witness the latest quarterly dividend distribution -- it came in at $0.58 per share, which results in a yield slightly below 6.6%. 

Banco Santander (ADR)

A clunky and ultimately unsuccessful CEO succession plan has sent Banco Santander's (NYSE:SAN) stock down nearly 30% over the past year. In 2018, the multinational lender offered its chief executive job to UBS executive Andrea Orcel. But the high salary he would have commanded was met with heavy criticism, and the bank nixed the appointment.

Another factor tamping the stock price down is that the bank is closely identified with its home country of Spain, whose economy has been a laggard for years. 

Yet Santander is a busy company with a very long reach, so at a fundamental level that CEO soap opera and the lifeless Spanish economy aren't dragging it down much. The company is very active in Latin America, for example, and also has a busy retail banking operation in the U.S. Several of those markets, particularly Brazil and Mexico, have been hot for its services recently.

These positive factors contributed to a 9% boost in euro revenue (in terms of constant currency) and a 32% improvement in attributable profit for Santander's 2018.

The upside to the depressed price of Santander's American depositary receipts (ADR) is that it has landed in high-yield dividend stock territory -- the stock, which pays a distribution on a quarterly basis, currently yields 6.2%.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.