The Economics Behind Gold's Recent Decline
Precious metals have fallen alongside essentially all other assets and the timing almost entirely relates to the Fed's recent policy statement. The Fed indicated that they would not be pursuing a much anticipated third quantitative easing program (QE3) as of yet:
Money Printing By the Fed: Chart of Assets on the Fed's Balance Sheet 
Instead, the Fed re-instituted a program called 'Operation Twist', which is designed to flatten the yield curve (make short term interest rates closer to long term ones) by swapping short term securities on their balance sheet for longer term ones in the open market. The unintended consequence of this policy is the minimization of the profits banks traditionally earn by borrowing at short rates and investing at longer, ideally higher yielding, maturities.
The lack of a balance sheet expansion by the Fed and the lack of incentives for banks to expand their balance sheets couples together to form a credit deflation threat. When credit unwinds, currency performs well because the actual quantity of liquid dollars in the system is outweighed by the credit structure built above it. The implosion of the house of credit leads to increasing demand pressure on its base, liquid money foundations and this is what drives up the price of dollars.
See the quantity of narrow money (Monetary Base) in existence versus total outstanding credit: 
When the blue line falls, the pressure on the red line, liquid dollars, is significant until the Fed comes around and prints up a ton of liquid dollars, or the demand wanes. What is likely to happen is that the Fed will print up a mass amount of currency AND the demand for dollars will fall, meaning precious metals will rise significantly as the dollar collapses over time.
Glossary of Terms
- Bullion
- Metal valued by its mass.
- Bullion Coin
- A coin valued by its precious metal content (typically with a purity of at least 90%) and used primarily for investment purposes.
- Commodity
- A product that exhibits some level of uniformity across suppliers.
- Diversification
- In finance or investing is a method of reducing risk by investing in diverse assets.
- Face Value
- The value inscribed on a coin (usually lower than its market value).
- Hedging
- In finance or investing is a method of reducing risk by investing in assets that exhibit an inverse relationship or are inversely correlated.
- London Bullion Market Association
- The trade association representing the wholesale gold and silver market in London and credited with setting the standards for the quality of gold and silver bars.
- Numismatic Coin
- A coin valued by its rarity, history or other characteristic of collectability.
- Numismatics
- The study or collection of coins, currency and closely related objects.
- Privy Mark
- Also called a “mint mark” is an engraving on a coin that denotes its mint of origin.
- Proof Coinage
- Collector coins that are fed manually, struck several times for superior quality and inspected by hand. Proof coins are minted in limited quantities and admissible in retirement savings accounts.
- Spot Price
- The quoted price of a commodity at the time of trading, usually only valid for one or two business days.
- Troy Ounce
- A standard unit of measure totaling roughly 31 grams.
- Uncirculated
- A term for coins that have been released to the public via mints or coin dealers but not intended to be used as every day currency.
- World Gold Council
- A market development organization, providing data and insights to gold-related industries including: investment, jewelry, technology and government.