The /s/ sound is spelled with <s>, <ss> or <ce>. The /ŋ/ sound is spelled with <ng>. Several pairs arise from assimilation of /n/ to /ŋ/ before /k/, such as risk/rink.
This is a contrast between a voiceless sibilant fricative and a voiced velar nasal continuant. It can only occur in final position or in a cluster and is fairly rare. It causes no problems.
The only taboo word pair is piss/ping.
Several pairs arise from a derived feminine noun in -ess and a participle, such as murderess/murdering. Other interesting pairs include:
office offing
witless whittling
The mean density value is 0.3%. The list makes 41 semantic distinctions, a loading of 81%.
adventuress adventuring axis axing basis basing bass bang brisk brink bus bung busing bunging busker bunker buskers bunkers coppice copping cornice corning countess counting dusk dunk gas gang gassing ganging gassed ganged heiress airing hostess hosting husk hunk husks hunks kiss king lettuce letting Lois lowing loss long misc mink morass meringue murderess murdering musk monk musky monkey notice noting office offing palace palling pinnace pinning piss ping pissing pinging redness reddening risk rink risks rinks service serving surface surfing suss sung Swiss swing testis testing treatise treating Tunis tuning whisk wink whisked winked whisking winking whisks winks whiteness whitening witless whittling
Credit: John Higgins