"The Pragmatic Capitalist" has excerpted a JP Morgan report sketching out how gold would do in a deflation. Since gold's price was fixed during the last deflationary bout, JP Morgan used the price of silver as a proxy. What they found was that silver fell along with stocks in 1929-33, but not as far; by 1934, unlike stocks, silver was higher than in 1929. Base metals fared worse.
The intimation is that gold would fall in a deflation, but would snap back and recover during reflation. Shades of '08-'09.