Gold has exploded above $4,000 an ounce, but that might not be the biggest news about the precious metal this week.

In what could be a seismic shift, Morgan Stanley has shaken up the traditional investment paradigm by ditching the conventional 60/40 portfolio and recommending a strategy that includes a 20 percent allocation to gold.

In this episode of the Money Metals Midweek Memo, host Mike Maharrey explains the ramifications of this shift, along with the reasons behind it. Along the way, he covers some of the dynamics behind this gold bull run and what it reveals about financial markets, money, and the economy.