1906: 1 Troy Ounce platina (Colombian ore, Spot, Est. 80%) = USD$ 18.
1906: 1 Troy Oz. Pt (Colombian export, .999) = USD$ 22.50
1906: 1 Troy Ounce Platinum (NYC: Refined, Spot) = USD$ 28.211906: 1 Troy Oz. Platinum (NYC Bid: Scrap) = USD$ 22.
Citation: The Jewelers' Circular, Vol. 81, Issue 2 p.89 (9/3/1920)
In 1906, Colombia reportedly exported 211.205 Kgs. platina
1906-7 Price Spike:
Citation: Mining American, Vol. 56, 11/14/1907 p.449
In 1906 (as 100 years before) free negroes were still bartering platina for presumably poor-quality and overpriced clothes and cheap trinkets. "They sometimes received money."
Citation: Mineral resources of the United States, Part 1 ; Geological Survey p.545
In 1906, the gold-platina yield was only ~10% platina.
The placer mining technology was still pre-Colombian.
Platina had been worthless for hundreds of years; even in periods of 19th Century European demand is was not aggressively sought after.