OIL.

It has fuelled the independence debate since it was discovered in the North Sea.

Whose oil is it? Did Westminster deliberately hide its true value? Is it running out? Can it pay for services in Scotland?

The questions surroun-ding the black gold are arguably the most intrig-uing of all in the debate and without it the discussion may never have happened.

Many people joined the SNP and the independence cause in the 1970s under the slogan "its Scotland's oil".

Anger that the revenue of the oil off Scotland was going to the UK Treasury when it could be spent by an independent Scotland led many to think Scotland should go it alone.

Forty years later, the failure of Westminster Governments to invest the money when production and prices were high is an argument put forward that the UK has squandered the oil wealth when Norway has built up a sovereign wealth fund of £500billion.

The UK, however, says the price of oil is volatile and the revenue has funded public services.

The current contentious issues centre on the amount of oil and how long it will last, with various projections bandied around by both sides, and how reliant Scotland would be on oil compared to the UK.

Nationalist supporters point to the McCrone Report, secret for more than 30 years, that contained advice that oil revenue could make an independent Scotland as rich as Switzerland, while the report also said if the price of oil collapsed it could be a disaster.

Which leads to the Better Together argument that the price of oil is too volatile for Scotland to rely on for income every year.

In its Scotland Analysis series the UK Government states: "Since devolution, offshore oil and gas receipts amounted to around 1.5% of the total UK receipts.

"For Scotland, North Sea revenues would have been almost 14% of the total.

"It is uncertain how an independent Scottish state, with a smaller economy and tax base, would manage the challenge of a narrower and more volatile revenue base."

Better Together leader Alistair Darling this week said: "Last year alone the North Sea oil revenues fell by about £4.5bn in one year.

"That's more than we spend on schools, it's getting on for half of what we spend on the NHS."

First Minister Alex Salmond counters by stating "oil is a blessing not a curse". He tells opponents "every other country in the world would give their eye teeth to have to have the oil Scotland has".

Mr Salmond says oil has been mismanaged by the UK for decades and it's time for Scotland to have "a turn".

In the White Paper Scotland's Future the Scott-ish Government states: "Westminster governments have also failed to reinvest the proceeds of the North Sea to provide a long-term benefit to future genera-tions. Stabilisation funds and sovereign wealth funds are common among oil and gas producing countries with the UK being a notable exception.

IN contrast successive Westminster governments have accumulated debts now in excess of £1trillion."

The UK Government states that Scotland as a part of the UK "achieves many of the benefits of an oil fund". It said: "The loss of the wider UK fiscal base could lead to an independent Scottish state being excessively dep-endent on oil and gas reve-nues, risking tax increases or spending cuts in order to provide additional income.

"If an independent Scott-ish state was able to radi-cally adjust fiscal policy and implement an oil fund, this would not smooth volatility in public finances."

Among the jargon, reports and predictions, it comes down to: would Scotland be too dependent on oil money as Alistair Darling says, or is it as Mr Salmond says, that oil equals wealth?

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