Geminate Consonants

[bbbourq]

Are there IPA representations for geminate consonants?

In my conlang, I have separate characters differentiating between a short and long consonant. There is a symbol which denotes an elongated vowel using the suprasegmental [ː]; however, I have not seen a specific symbol used with consonants (perhaps mː ?). Arabic has the shadda which denotes a double consonant which alone can make the difference between two words and is usually pronounced accordingly. Unfortunately, not all languages pronounce a double consonant differently over a single consonant (cf. English lighter vs. better or German Kater vs. Mutter.)

I apologize if this has been discussed previously, but my searches have not produced adequate results.

[Yng]

The colon (or slightly modified colon) is used for geminate consonants as well as long vowels. You could also write the consonant twice if that makes sense.

[Zaarin]

Yes, <ː> is the symbol you want, for consonants as well as vowels. Note that /mː/ and /mm/ are not necessarily the same thing and can contrast: you could have a hypothetical /amː.a/ vs. /am.ma/, for example. (I've always been fascinated by languages like Berber that feature word-initial long consonants...)

[bbbourq]

Brilliant! Thank you both for the guidance. I just needed a way to accurately represent the pronunciation as best as I can. I will incorporate this into my lexicon.