Glad that someone else has an interest in these. What you have doubtlessly seen cited in many sources is that mint workers were displeased by the dull appearance of the 1902 mattes just after striking and so sought to improve appearances by a swipe on the mint apron (I really have no idea of the veracity of this, but does somewhat explain the appearance of many hairlines 1902 mattes of all denominations). This seems to imply that the matte surface was due to planchet and/or die prep PRIOR to striking.
Quite a few of the matte proofs struck AFTER 1902 have evidence of "sandblasting" post minting.Somewhere I have I believe it is the 1951 2/6 matte with residual blasting medium adherent to the devices and lettering on the reverse especially.
The 1924 silver satin/matte specimens seem to be unique, and Steve Hill agrees, in that a plating was applied to the planchets PRIOR to striking (evidently some of the surface delaminating prior to and then subsequent to also minting & thus appearing a bit rude with commiserate low grades). Thus they really should probably not be considered matte, and making them quite different than the satin specimen 1965 Churchill Crowns, whose appearance IMHO is likely due to pre strike planchet preparation and likely die prep also.
I tend to agree by most peoples' definitions that the 1935 Jubilee medals in large and small format would be considered matte proofs. I have not seen any crowns of that year of similar appearance - I am sure if found that they would go for a fancy sum.
I have probably forgotten most of what I used to know about the mattes. Not that it matters but I do not believe the TPGs really care or understand any of this and have grades that are a bit willy-nilly. This would not matter except the prices fetched are very much driven by the grade on label which drives me up a tree. They are completely unamenable to any discussions and the graders remain anonymous.