As long as it's only grime and not pen marks or anything of the sort (though I had one of those on my ivory MJ but that's a long story), Coach leather cleaner should work great.
Get the two-pack that has the leather cleaner and conditioner. The last time I bought some it came in a pretty plain brown box, but the stuff lasts forever so it's been a while. The bottles have instructions, basically use a non-abrasive cloth, clean first then condition. But you can use one or the other as needed. HTH, your blake is beautiful!
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