“ I have only just received a reply from Johnson Matthey to my inquiry about the historic platinum prices you wanted. Please see attachments for research resources.”

Eoin Treacy's view In Comment of the Day on November 9th I mused that since we did not have access to platinum prices spanning the last major bull market in precious metals it was impossible to know whether parity between platinum and gold was likely to continue to offer an area of support for platinum. I sent out a couple of emails inquiring after long-term data for and was delighted to receive Martin Spring's above email contributed in the spirit of Empowerment Through Knowledge. Johnson Mathey's data allowed me to draw two useful charts. One is a long-term overlay of annual average gold and platinum prices, the other is a long-term ratio of the two data sets.

The platinum prices in these charts are annual average prices for 1946 to 2011. I manufactured annual average prices for gold by taking a simple average of monthly closing prices. It should be noted of course that these average annual prices dispense with a great deal of intra-year trading activity.

This long-term overlay charts highlights a major bull and bear market in platinum while gold prices were still held static within the Bretton Woods agreement. Platinum prices surged in the early 1960s and gave up much of the advance before embarking on another advance more or less in line with the gold prices during the 1970s.

Since 1974, average platinum/gold prices have broadly ranged between 1 and 2. This trading range has held through both major bull and bear markets for the respective metals. Therefore it is reasonable to suggest that the area of parity is more likely than not to offer support for platinum relative to gold on an average annual price basis.

In nominal terms, the ratio has been trending lower for the last year and will need to sustain a move back above 1 to indicate platinum is returning to relative dominance.