Johannesburg’s benchmark stock index is heading for its worst month in almost two decades, reeling from a double hit as the Iran war saps demand for emerging-market assets while plunging precious-metal prices weigh on the country’s miners.

The FTSE/JSE All Share Index was down 13% in the month through March 27 at the close on Friday, the most since the height of the global financial crisis in September 2008, according to data compiled by Bloomberg. That’s a sharp turnaround after the gauge logged 12 straight monthly gains through February, the longest streak on record.

The precious metals and mining sector, which accounts for a quarter of the index’s weighting, has tumbled 27% since the start of the Middle East conflict, wiping out this year’s gains as gold and platinum prices slumped. That came amid a broad selloff of emerging-market stocks as investors fret that the spike in oil prices will fuel inflation, forcing central banks to raise interest rates.

“Profit-taking in precious metals counters on de-risking has amplified the hit on South African equities,” SBG Securities analysts Deanne Gordon and Adele Fermoyle wrote in a note.

South African stocks had been one of the big winners of the past year, jumping 43% in the 12 months through February in a rally helped by a meteoric surge in gold prices and signs of cooler inflation.

But with oil prices topping $100 a barrel and the war in the Middle East putting a chill on investor sentiment, investors have quickly unwound those bullish bets. The losses now mean South African stocks rank among the worst in the world, with only Dubai, Indonesia and Korea falling more since the start of the war.

It’s not only miners that have plunged. Construction and materials, retailers and banks are among sectors that have fallen more than 10% this month.

Some investors remain positive on South African stocks, seeing this months’ decline as an opportunity to add exposure. SBG Securities in March reiterating its overweight view on South African stocks, with analysts pointing out that foreign investors were still net buyers of South African stocks year-to-date.

“Within Africa the JSE usually reacts negatively in the first phase of a conflict like any risk market but over time it often holds up better than many other African exchanges thanks to its depth, its liquidity and its large resource exporters,” said Cedric Beguier, the head of investment strategy at Mauritius-based AXYS Group.

But an extended conflict in Iran would stymie any potential recovery as sustained high energy prices fuel inflation. The South African Reserve Bank last week lifted its inflation forecasts and warned that a prolonged war would lead to higher interest rates, which would weigh on economic growth. That would likely deepen the selloff to sectors other than mining, according to Avior Capital Markets.

“In a risk-off environment, emerging markets and South Africa fall out of favor,” said Adrienne Damant, an analyst at Avior. “Retailers, banks, property and insurers will be negatively impacted by higher interest rates and low growth.”