In the world of crypto investing, Bitcoin (BTC-USD) is the top dog, and has remained so since its inception 13 years ago. However, crypto mining stocks have also become popular among investors in digital currencies, particularly those tied to the “mining” of Bitcoin.

Bitcoin mining is often viewed as some opaque subject that’s difficult to understand. In many ways it is. Through solving various complex cryptographic puzzles, miners receive the ability to mint a block, and the rewards that come along with doing so.

This mining activity takes a tremendous amount of computing power, and has become increasingly centralized. Back in the good old days (roughly a decade ago), most mining was done by individuals in their basements. Today, it’s massive computing farms owned and operated by a few companies.

Thus, scale has become important. And these companies have found ways of growing their hash rate over time in the most profitable manner. Accordingly, for investors looking at crypto mining, these stocks are the ones often looked at.

However, with the market in turmoil (driven by declining Bitcoin prices), there is certainly risk in this space. Investors looking at these stocks ought to consider this risk before diving in.

With that said, here are three crypto mining stocks trading at an impressive discount that may be worth considering for aggressive growth investors.

Riot Blockchain (RIOT)

One of the largest Bitcoin miners in the U.S, Riot Blockchain (NASDAQ:RIOT) is often a top pick of investors for this reason. Thus far, the U.S. has been one of the more stable places for crypto miners to set up shop. In this regard, Riot has an upper hand on its competition, to some degree.

Riot Blockchain specializes in Bitcoin mining operations in North America. The company runs through three major segments — Data Center Hosting, Electrical Products and Engineering and Bitcoin Mining.

In June this year, Riot generated 421 BTC — an approximate hike of 73%. As of June 30, 2022, Riot held roughly 6,654 BTC, and all of them were formed by its self-mining operations. Also, in June, Riot sold 300 BTC, producing net proceeds of around $6.2 million.

By January 2023, Riot expects 12.5 EH/s as total self-mining hash rate capacity — assuming complete deployment of around 115,450 Antminer ASICs.

As Riot approaches its next earnings release, Wall Street is hoping for strength from the company. Zacks Consensus Estimate calls for quarterly revenue of $82.95 million. That’s up 141.48% from the same period last year.

Hive Blockchain (HIVE)

Hive Blockchain (NASDAQ:HIVE) is another top Bitcoin miner. However, in addition to Bitcoin, Hive also mines Ethereum (ETC-USD) and Ethereum Classic (ETC-USD).

Accordingly, from a diversification standpoint, there’s a reason why many investors like Hive relative to its peers.

Beyond this, Hive has posted some very strong results lately. The company’s recent full-year results showed revenue growth of more than 212%. A record net income of nearly $80 million capped off the year, showing 43% year-over-year growth.

Now, much of these gains have to do with the volatile, yet higher, crypto prices that prevailed through the end of last year. Accordingly, it’s expected Hive’s forward numbers won’t be as good.

That said, Hive’s impressive capacity is something crypto bulls have pointed to as a reason to own this stock. The company has increased its capacity to roughly 6,100 GH/s of ETH mining and a massive hashrate of 2 Exahash in March 2022. As a reference, it was around 2,700 GH/s of Ethereum mining and 310 PH/s of BTC mining as of Q1 2021. That’s 225% growth in Ethereum mining hashrate and 545% growth in Bitcoin mining hashrate year-over-year.

Marathon Digital (MARA)

Last, but not least, we have Marathon Digital (NASDAQ:MARA). Marathon Digital is a massive digital asset company, focusing on blockchain development, the creation of digital assets and, of course, crypto mining.

In early March, the company announced the production of more than 360 Bitcoin in a single month. This translates to a year-over-year growth rate of 729%. Not too shabby at all.

Like its peers, Marathon has been investing heavily in its mining infrastructure. This has allowed Marathon to increase its total Bitcoin holdings to nearly 9,000 tokens. At today’s prices, that’s worth just under $200 million.

Thus, at a market capitalization of approximately $1.2 billion, Marathon is now trading around 6-times the assets on its balance sheet. Notably, these digital assets are volatile (hence the newfound discount on MARA stock). However, should another bull market be around the corner, this valuation could turn out to be very attractive in hindsight.

On the date of publication, Chris MacDonald did not have (either directly or indirectly) any positions in the securities mentioned in this article. The opinions expressed in this article are those of the writer, subject to the InvestorPlace.com Publishing Guidelines.