True. If you mine a coin and the price is $1.00 that is gross income. The question is if you are getting paid out 50-100 times a month, it gets really hard to track. What I do is recognize the income once a month at the same exact time / day every month. Basically on the 28th at 5PM (my timezone). Any coin I mined that between the previous date and this date I value at the market price from the same place every time. It is a pain, but easier than doing it 100 times a month.
I read on Intuit's site, if you receive gains from something you sell from within your business, then it isn't capital gains at all but actually considered revenue income and taxed same as income tax rate, and that the revenue income is subject to self employment taxes (after any expense deductions).
Cryto-assets are capital assets.
Long Term Asset = Held for 12 months or longer
Short Term Asset = Held for less than 12 months
I'm not 100% sure if this changed with the new US tax law but...
If you were in the bottom 2 brackets, you pay 0% capital gains on long term assets.
If you are in the top bracket, you pay 20% for long term capital gains.
If you are in the middle of those two, you pay 15% for long term capital gains.
Short-term capital gains are taxed at if they are income.
Some examples...
You mine $100 worth of coin and hold it for 13 months. Sell it for $150. You pay income tax in the year you mined it for $100. You pay capital gains on $50 when you sell it assuming you held it for 12+ months.
You buy 6 video cards for $400 each ($2400). You mine them for 13 months and then sell them for $500 each ($3000). You pay capital gains on $600.
You buy 6 video cards for $400 each ($2400). You immediately sell them on craigslist for $650 ($3900) [you jerk]. You pay income tax on $1500.