As the only polyhalite miners in the entire world, Cleveland Potash says it can satisfy global demand for the fertiliser within five years.
If this is true, what does the future hold for York Potash, which plans to construct a second mine within the national park, solely to exploit same product?
For many, last week’s announcement that Cleveland Potash was to begin marketing polyhalite was seen as a U-turn, as the company had objected to the York Potash planning application on the basis that there was no demand for the mineral.
General manager Phil Baines explained studies into the alternative fertiliser polyhalite have actually been going on for years and said: “If you wanted I could send you one thousand tonnes right now. York Potash can’t do that.
“But if this stuff is so good, why aren’t people knocking on our door right now?”
Studies show up to a billion tonnes of polyhalite sit below the Yorkshire coastline, and Mr Baines said the company owed it to its employees to discover what potential there is for the sale of this product.
He added: “A billion tonnes is incredible, it’s unheard of. It’s 150 years’ worth.
“I’m not really bothered about Sirius Minerals at all. My concern is solely towards the success of Cleveland Potash and if polyhalite can contribute to our success then great.”
With Cleveland Potash set to add polyhalite to its list of products, does the North York Moors planning authority believe this strengthens the case against building a second mine?
Planning director Chris France must remain tight-lipped on the projects, due in part to the pre-planning agreement in place with York Potash.
However a York Potash spokesperson said: “Imitation is the best form of flattery, so we wish Cleveland Potash every success in helping to create jobs and establish the UK as the world leader in this high quality form of potash.”
Mr Baines explained how the polyhalite seam which runs under Boulby is the same as that which the York Potash project hopes to exploit.
However, far from just linking the two mining projects, the reserve is potentially as large as Western Europe as it sits at the bed of an ancient ocean, known as the Zechstein Sea.
So is it necessary for the York Potash mine to be built within the national park?
Since the early days of Boulby mine, the company has known that vast swathes of polyhalite sit just 150ft below the potash seam.
Yet this has not been exploited at Boulby as there has been no market for the polyhalite. With it containing just 25% of the potassium that is found in potash, farmers have so far not been convinced that they should make the switch.
For £40m Cleveland Potash can extract the material, but the estimated costs of the York Potash project are £1bn.
Therefore, while the potential market is being explored, the risk is substantially lower for Boulby than it is for Sirius.
“It gives us potential flexibility with our business,” explained Mr Baines. “If we can develop a market for the stuff.”
In five years Boulby believe they can extract 600,000 tonnes of polyhalite per year, of which around half is the ‘course’ grade that farmers find more attractive.
Mr Baines said this would satisfy the current global demand for polyhalite, something York Potash disputes.
A spokesperson for Sirius said: “The facts of the market speak for themselves and are demonstrated by the commitments we already have for 4.8million tonnes per year.”
If York Potash are correct and Cleveland Potash has underestimated the market, will Boulby ever switch to a completely polyhalite mine?
“I can’t see it,” said Mr Baines. “Farmers can be fixed in their ways so if potash works, why should they change?”