Donald Trump's two sons have taken a financial stake in a mining venture that last year secured up to $1.6bn in US government-backed financing to develop what is described as the world's largest undeveloped tungsten deposit in Kazakhstan — a project that received direct personal support from the president, the secretary of state and the commerce secretary, according to a company investor presentation.

The Financial Times reported on April 31 that Donald Trump Jr and Eric Trump invested in Skyline Builders Group Holding (Nasdaq: SKBL), a US construction company, last August through a special purpose vehicle called American Ventures, a subsidiary of Dominari Holdings (Nasdaq: DOMH).

On April 30, Skyline merged with Cove Kaz Capital Group, the mining entity developing the Kazakhstani tungsten projects. The combined company, to be named Kaz Resources Inc, plans to list on Nasdaq under the ticker KAZR. The merger announcement did not mention the Trump brothers.

A spokesman for Donald Trump Jr told the FT that he "does not interface with the federal government on behalf of any company he invests in or advises." Eric Trump did not respond to a request for comment.

The deal's timeline

On September 22, Kazakhstan's president Kassym-Jomart Tokayev told Donald Trump he intended to award a major tungsten mining project to US investment group Cove Kaz Capital, which had been competing against Chinese and Russian companies for the concession. Details of the presidential conversation leaked to the press on October 21.

Seven days later, on October 28, the Trump brothers invested further money in Skyline as part of a capital increase of just under $24mn.

Three days later, on October 31, Skyline agreed to pay $20mn for a 20% stake in a company described in regulatory filings as having "significant holdings of critical minerals in Asia" — which proved to be Kaz Resources, a subsidiary of Cove Capital.

On November 6, at the C5+1 Leaders' Summit in Washington, Cove Capital and Kazakhstan's national mining company Tau-Ken Samruk officially announced the deal to develop the Northern Katpar and Upper Kairakty tungsten deposits in the Karaganda region of central Kazakhstan.

Under the terms, Cove Kaz controls 70% of the project and Tau-Ken Samruk retains 30%. Planned investment is $1.1bn.

US government financing followed. The Export-Import Bank of the United States issued a letter of interest for up to $900mn in project financing. The US International Development Finance Corporation issued letters of interest for a further $700mn. Together, the two federally backed institutions committed up to $1.6bn in support — making it one of the largest US government-backed critical minerals financings on record.

Cove Capital chief executive Pini Althaus told the FT that Cove had received "direct support from President Trump, Secretary of State Marco Rubio, and Commerce Secretary Howard Lutnick" to secure the mine. Lutnick sent a personal letter to Kazakhstan's president in support of the deal, according to an investor presentation filed with the US Securities and Exchange Commission.

There is no evidence that the Trump brothers were aware of Cove's pending $1.6bn US government commitment when they made their initial investment in Skyline, nor that they played any role in the contract's award, the FT reported.

Why tungsten

The strategic logic of the deal is straightforward. Tungsten is the metal with the highest melting point in the world and is critical to a wide range of defence applications — armour-piercing ammunition, kinetic interceptors for missile defence, hypersonic weapons, F-35 engines and semiconductor manufacturing. China controls over 80% of global tungsten production.

In February 2025, Beijing imposed export restrictions on the metal, driving the price of ammonium paratungstate — the international benchmark — up by more than 40%. The United States closed its last domestic tungsten mine in 2015.

"The Pentagon wants tungsten at any price," said Christopher Ecclestone, a mining strategist at Hallgarten in London, told the FT.

The Northern Katpar and Upper Kairakty deposits contain a JORC-compliant mineral resource of 1.4mn tonnes of tungsten trioxide — approximately 70% of Kazakhstan's total estimated tungsten resources and roughly 58% of China's 2.4mn tonne reserve as calculated by the US Geological Survey.

The broader pattern

The Kazakhstan deal is not the only instance in which Trump family business interests have intersected with US government contracts in the first year of the president's second term.

In August 2025, a venture capital firm called 1789 Capital invested in Vulcan Elements, a rare earth magnet manufacturer in which Donald Trump Jr holds a partnership stake. Three months later, Vulcan received a $620mn Pentagon loan — described as the largest ever granted by the Pentagon's strategic capital office — plus $50mn as a government equity stake. An executive order signed by Trump had previously lifted the requirement for independent technical review of such awards.

In March 2026, the Trump sons invested in a drone manufacturer called Powerus, which has since been pursuing contracts from a US government drone programme with a budget of $1.1bn.

Democrats in Congress attempted to compel Donald Trump Jr to testify under oath about the Vulcan deal via a congressional subpoena in March 2026. The committee vote was blocked by Republican members.

The Wall Street Journal has estimated that Trump family businesses have generated at least $4bn in revenues and paper wealth since the November 2024 election, spanning cryptocurrency, defence technology, rare earths, tungsten and prediction markets.

Neither the White House nor the Trump Organisation responded to requests for comment.