If there's a prevailing theme for investors this year, it's volatility. Always present in the stock market, volatility has been especially pronounced in 2020 on the heels of the coronavirus disease 2019 (COVID-19) pandemic. The benchmark S&P 500 lost a third of its value in roughly a one-month span during the first quarter, then recouped all of its losses under five months. That's a decade worth of volatility crammed into just six months.

Though volatility can be worrisome at times, it also represents a bona fide opportunity for long-term investors to put their cash to work. Historically, every stock market correction and crash has eventually been erased by a bull market rally. As long as investors give their investing thesis ample time to play out in a basket of innovative companies, they usually come out ahead.

Best of all, building wealth in the stock market doesn't require you to start with a mountain of cash. If you have $500 that won't be needed to pay bills or cover emergencies, you have more than enough to buy the following three great stocks, all of which can make you richer.

Five one hundred dollar bills neatly layered on top of each other.

Image source: Getty Images.

TJX Companies

You might think I'm insane for suggesting that any investors put their money to work in a predominantly brick-and-mortar retailer, with the COVID-19 pandemic case count worsening again in North America. But ignoring any sale on the shares of TJX Companies (NYSE:TJX) has historically been a mistake.

TJX is the parent company behind popular retail chains T.J. Maxx, Marshall's, and HomeGoods. Its long-term success is due to consumers' love of brand-name items. TJX Companies specifically seeks out deeply discounted brand-name merchandise that other retailers or wholesalers are looking to move, then retails this merchandise at a steep discount to its shoppers. TJX's ability to buy in bulk also helps to reduce the price of what it pays. Because of its ability to scale and throw its weight around, TJX can offer huge discounts on its clothing and accessories to lure in bargain shoppers, yet can still walk away with killer margins.

Maybe the craziest thing of all is that TJX is generating nearly all of its growth from its physical stores. Online sales have almost certainly increased since the COVID-19 pandemic struck but represent only a small fraction of total sales. This is a company that envisions increasing its total store count by another 1,500 physical locations, to over 6,000. 

Retail stocks may be cyclical, but TJX Companies is a good bet to emerge from the coronavirus recession stronger than it was before.

A one ounce silver ingot on a dark background.

Image source: Getty Images.

First Majestic Silver

Another great stock to consider buying that's probably off the radar for a vast majority of investors is Mexico-focused mining stock First Majestic Silver (NYSE:AG).

One catalyst for First Majestic is that its underlying metal should see favorable headwinds in the years that lie ahead. Silver typically performs very well in the first year or two following a recession. That's because silver rides the coattails of gold higher during the period of economic uncertainty that accompanies a recession. It then tends to outperform gold during the initial stages of the recovery as physical demand picks up -- silver is used in a number of industrial and technology applications.

More specific to First Majestic Silver, the company has placed a handful of higher-cost mines on maintenance and care, with the costs for these assets expected to diminish significantly after 2020. Meanwhile, its three remaining assets -- San Dimas, Santa Elena, and La Encantada -- are expected to see more efficient output at lower all-in sustaining costs (AISC). After encountering numerous operational hiccups, my expectation is that AISC could dip below $12 per ounce in 2021, with operating cash flow soaring on the heels of higher realized metal prices and improved mine yields.

Silver stocks have a real chance to shine in the early stages of the recovery, which should bode well for First Majestic Silver.

A person using a tablet to peruse a pinned board on Pinterest.

Image source: Pinterest.

Pinterest

If big-time growth stocks are more your thing, social media up-and-comer Pinterest (NYSE:PINS) looks to have the tools to make its shareholders richer.

As you might be aware, Pinterest reported its third-quarter operating results last week and absolutely crushed Wall Street's expectations. It's been helped by the COVID-19 pandemic, with more people going online to satisfy their entertainment needs, as well as by the advertisers boycotting Facebook during the third quarter.

Pinterest ended September with a hearty 442 million monthly active users (MAU), which is up 120 million from September 2019. Approximately 90% of these net MAU gains are derived from international markets. Though average revenue per user (ARPU) in overseas markets represents just a fraction of the ARPU that Pinterest is generating from U.S. MAUs, the company has demonstrated that there's incredible upside in growing ad revenue for international MAUs. The $0.21 international ARPU reported in Q3 2020 ties the company's all-time high for overseas ARPU in a quarter. 

Pinterest also stands to benefit from its e-commerce push. Since its users are willingly posting about the products, places, and services that interest them, it only makes sense for Pinterest to connect these users with small businesses that cater to these needs. As long as Pinterest can keep its users engaged, high double-digit growth could be the expectation for years to come.

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.