What Do The Color Crayon Markings On Covers Mean ?

I've seen these markings lots of times,mostly in blue pencil or crayon but sometimes I see purple,black,green,red,brown etc.Sometimes even canceled stamps done by crayon,I've searched the internet and old posts here but really can't find an article on what color is actually used for,I know blue is for postage due(I think) and most canceled stamps are done with brown.

Does anybody actually know ?

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can you post some pictures...

If you are talking about crayon markings like on my cover below, the 1802 is the post office box number of Mr. S Chapman.

A large blue cross, or crossed lines across the cover indicates that it is a registered piece of mail in regards to the older British Commonwealth covers, if I remember correctly.

A capital "T" marked with crayon or stamped indicates postage due. The amount due is usually written, also.

Hi,yes just the the cover that littleriverphil posted,but I was wondering why different colors are used,green,red,brown blue etc,I read an article that different colors were used for different purposes but that was a while ago and I can't remember where it was,I think it said different things like postage due,canceling a stamp etc had to be done with certain colors,some kind of post office rule,like blue is for registered covers,"red is to mark ?" "green is to mark ?",know what I mean.

There was a color code before prepayment of postage was mandatory. But after stamped mail, I think they used what was handy. The Taunton PO used a red pencil to note that this Mendocino cover was not called for after it was advertised.
On the Forwarded Willits cover it was grayish black and purple.

I think in most cases these are colored pencils being used rather than wax crayons.