File extension and Internet media type for a non-standard file format

Question

For CSV(Comma-separated values) the file extension is .csv and the Internet media type is text/csv .

For TSV(Tab-separated values) the file extension is .tsv/.tab and the Internet media type is text/tab-separated-values .

The 2 above statements are well known due to some existing standards. My question is - for a delimited text file which uses as delimiter the colon(:) which should be the file extension and the Internet media type? Is there a known way for deciding the correct file extension and the Internet media type for a text format which doesn't have a defined standard? I searched for this, but I couldn't find anything useful.

Answer 1

That would still be a CSV file, albeit with a different separator character.
There is, to my knowledge, not a specific mime-type defined for this.

There does exist a mime-type for CSV-SCHEMA which is a way to describe the structure (including separator) of CSV files in a generic way.

See the IANA list of mime-types here and the description of the CSV-SCHEMA format here

Answer 2

Media types are used to tell a browser or other software what type of data is contained in the file and how it is supposed to be opened or handled.

so this is text data (no matter what delimiter is used), you can simply label it as 'text/plain' or something similar, unless you want browsers or client software to do some special handling with that delimiter.

Here is a list of MIME types for Text, you can check and see if there is a type of particular interests:

http://www.iana.org/assignments/media-types/media-types.xhtml#text

and there is an similar question on StackOverflow:

https://stackoverflow.com/questions/3828352/what-is-a-mime-type