To many, stocks, gold and crude oil are three very different markets. Stocks prices essentially measure optimism through corporate profits, with a bit of central bank management mixed in for good measure. Gold, has a 5,000-year track record where one holds a physical asset that has no meaningful financial liability. Crude oil prices reflect something like the blood pressure reading of the economy. New technologies have changed the oil formula somewhat, but at about 81 million barrels per day, the underlying symptoms are easily identified and continue to be the same.
However, there remains two commonalities: These are that demand still matters, and all three are priced in dollars. With few exceptions (China trying to be an exception), you need a dollar to buy any of them.