Here is Truly who is a grey you you can see that she is all white now that she is older (greys get whiter as they get older). Truly was born chestnut in colour and started going grey as a yearling. Also Truly has black skin rather than pink or mottled skin (I love a nice dappled grey!).
Greys also don't have those varnish markings.
But you will see that Truly has small chestnut flecks on her body - those are called flea-bits - she is a Flea-bitten Grey. Those differ from a Leopard Appaloosa which have large round spots all over their body.
I had a leopard appy but I don't have any photos here on site (but I am sure you can google leopard appaloosa).
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