@PaintItPretty: I am afraid it isn't and I am even more afraid that it may turn out to be a product you will not be able to get.
The main difference being, that Creme fraiche is made from pasteurised, soured cream, whereas clotted cream is made from raw milk, then ever so gently heated, evaporating water and leaving behind little but butter fats and protein. Do make a point of looking at the Wiki page, allthough their mention of a minmum fat content of 55% is regarded as a joke in the UK. Proper Devonshire Clotted Cream will always clock up an easy 66%, if not more. It is literally heart attack in a tub. Even a single tablespoon full of the stuff will give you all the saturates your body can handle in a week. You may have heard of
Cream Teas. A scone with a thick layer of clotted cream and then fresh strawberry jam on top. The cream is so thick, it can only be spread with a knife. This is the way they do it in Devon, the Cornish way is different, so you might like to look at the Wiki link I've embedded in the text.
This reminds me, if you can get it, try Whey Cream Butter. Wiki has a good graphic of all the uses of milk here:
Milkproducts
To make it, the milk is first semi-coagulated with rennet, pretty much the same process that is used in cheesemaking, which adds an amazing, yet subtle cheesy flavour to the butter. It is more expensive, about 20%, but well worth the money.
I guess, apart from the Irish and those living on the Channel Islands of Jersey, Guernsey and Alderney, we must have some of the richest milk in the world. Grazing in Britain is fantastic and even better in Ireland, after all, all that rain did give it the nickname 'The Emerald Isle'.