The Fed Raised Rates 0.25 Points for the First Time Since 2023 and Gold Closed 85.65 Dollars Higher the Next Day; Tehran's 18 Karat Gram Fell 138,300 Tomans in the Same Window (Friday, 18 September 2026)

The US central bank raised its policy rate by 0.25 percentage points on Wednesday, 16 September 2026 (25 Shahrivar 1405), its first increase since 2023. The textbook rule says higher rates are bad news for gold, which pays no yield. In Sahmino's own recorded series, however, spot gold closed the decision day at $4,257.83 and closed the next day, Thursday 17 September, at $4,343.48: $85.65 and 2.01 percent higher.

Background

The decision came in a week of three major central bank meetings. The Bank of Japan raised its rate to 1.25 percent, a 31 year high (Al Jazeera, 18 September 2026), and the Bank of England held at 3.75 percent for a second consecutive meeting while warning of upside inflation risk (Bank of England, 17 September 2026).

The run into the decision had not been kind to gold. On Sahmino's recorded series, spot gold closed at $4,664.08 on 25 August 2026 and had fallen to $4,257.83 by 16 September. Trading Economics, in its 18 September 2026 report, notes that gold has fallen 3.10 percent over the past month and that the week ending that day was its first weekly gain in four weeks.

The numbers

Every figure below is dated, and its source is named in the same line.

• US policy rate: raised 0.25 percentage points at the Wednesday 16 September 2026 meeting, the first increase since 2023 (Trading Economics, 18 September; Kitco, 17 September; TGJU, 17 September).
• Spot gold, Sahmino's recorded series: $4,257.83 on 16 September 2026, $4,343.48 on 17 September. Difference: $85.65, or 2.01 percent.
• Spot gold, live reading on 18 September 2026: $4,377.52 (Trading Economics), which is $119.69 and 2.81 percent above the decision day close.
• Tehran 18 karat gold, Sahmino's recorded series: 23,501,300 tomans per gram on 16 September 2026, 23,363,000 tomans on 17 September. Difference: 138,300 tomans lower, or 0.59 percent.
• Free-market dollar (dolar-e azad, the rate ordinary Iranians transact at), Sahmino's recorded series: 230,500 tomans on 16 September 2026, 227,900 tomans on 17 September, 1.13 percent lower. TGJU recorded the same 227,900 toman rate that day.
• Brent crude: a third consecutive lower session to 18 September 2026, at $104.29 (Trading Economics).

Those last two figures are what invert the story for an Iranian reader: in the same window in which the ounce rose 2.01 percent, Tehran's 18 karat gram fell 0.59 percent, because the free-market dollar retreated by more than the ounce advanced.

What drove it

A price moving after a decision is not the same as that decision causing it. Several other things changed inside the same window, and market sources credit those rather than the rate increase itself.

Kitco, in its morning report of 18 September 2026, writes that lower crude oil prices, easing Treasury yields and a softer dollar helped precious metals extend their post-Fed rebound. CoinDesk, on 18 September 2026, reports the US 10 year Treasury yield back below 5 percent. Trading Economics likewise attributes support to falling oil prices easing concerns over prolonged inflationary pressure, while noting that gains were capped by a stronger dollar.

On the decision itself, Natixis economists Christopher Hodge and Selin Aker, in a note cited by Kitco on 17 September 2026, characterised the FOMC vote as "the path of least resistance" and said another increase could come before year end. Trading Economics, the same day, cites market pricing of a nearly 60 percent chance of a further increase next month.

The transmission into the Tehran market is straightforward: the local gram price is built from two inputs, the global ounce and the free-market dollar rate. When the ounce rises and the dollar falls by more, the gram gets cheaper. We saw the same mechanism running the other way in our report on the divergence between the global ounce and Tehran gold, where the ounce was almost flat and the Tehran gram rose.

Outlook

This section is analysis, not reporting. As long as the US 10 year yield stays below 5 percent and oil keeps falling, the pressure on gold from policy rates is smaller than the headline of the decision implies. Against that, if the second increase the market prices at roughly 60 percent does arrive, that yield rises again. The practical point for an Iranian reader is that the ounce is only one of the two inputs to the Tehran gram price, and in recent days the free-market dollar has been the more volatile one.

Bottom line

The Fed raised rates on 16 September 2026 for the first time since 2023 and spot gold closed $85.65 higher the next day, the opposite of what the rule of thumb promises. The reason was not the rate increase itself: inside the same window oil fell for three consecutive sessions and the US 10 year yield returned below 5 percent. If one thing survives from this report, it is this: do not read a central bank decision without reading what moved alongside it. Our reading is that spot gold stays above $4,300, as long as the US 10 year yield stays below 5 percent, with a horizon to the end of Mehr 1405 (22 October 2026); and if the ounce closes below $4,300 before the end of Mehr, that reading is broken.

What to watch

• The US 10 year Treasury yield, and whether it stays below 5 percent.
• The next Fed meeting and that roughly 60 percent probability of a second increase; announced dates are tracked on Sahmino's economic calendar.
• The balance of the two inputs to the Tehran gram price, the ounce and the free-market dollar, whose latest rates update on Sahmino's prices page.
• The Emami coin premium (hobab, the gap between market price and metal value), which usually reacts sooner than the gram when the ounce and the dollar move in opposite directions.
• Brent crude, which was one of the two stated reasons for gold's rebound in this window.