As strikes and mining disruptions in South Africa, the world’s largest platinum producer, continue, physically backed platinum exchange traded fund holdings have surged with holdings rising to record highs.

Platinum ETFs now hold a record 2.215 million ounces of the white metal, or about seven months in supply, Reuters reports.

The Johannesburg-listed NewPlat ETF (NGPLTJ.J), the world’s biggest platinum ETF, added 4,000 ounces of platinum Monday, bringing total holdings to a near seven-week high of 908,811 ounces

Meanwhile, London-listed ETFS Physical Platinum (PHPT.L) raised platinum holdings by 4,505 ounces to a little below 325,000 ounces.

In comparison, the U.S.-listed ETFS Physical Platinum Shares (NYSEArca: PPLT) is backed by 526,618 ounces of platinum.

Physically backed metals ETFs are a type of investment vehicle that issue securities backed by the physical metal stored in vaults. Consequently, each share of PPLT has an approximate value of 0.0975 ounces of platinum.

Platinum prices are now hovering around $1,463 per ounce, rising 7% year-to-date.