is there a silent ringtone available

Silent ringtones can be found in the iTunes Store. They are also easy to create with GarageBand or iTunes (they are just blank audio files). .

If you want to make your own there are tutorials online. You just need to record a silent (no input) *.m4a file in iTunes or GarageBand or even QuickTime player could do it. Then change the file extension to *.m4r and import it into iTunes then onto your phone to assign as a custom ringtone to contacts. Just make the silence recording of 30s or less.

Hey horhay24,

You're wanting to know if there is a "Silent" ringtone. There isn't a "Silent" ringtone. If you would like to submit feedback to Apple, you may do so here: Product Feedback.

Cheers.