I created a simple RTF file in MS Word. I then added the Title and Author metadata using calibre and converted the file to MOBI using calibre. Title and Author both show up okay on the Kindle.

I attached both files. I added no metadata directly to the RTF, but added it to the MOBI prior to converting.

Also to confirm, the Kindle cannot read native RTF. It has to be converted to MOBI.

EDIT: You will notice that the RTF file is several times larger than the MOBI. This is partly due to the nature of RTF, but it also has to do with MOBI not being as robust as far as formatting goes.

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