Claim: Florentine and Tuscan can be distinguished from Standard Italian by differences in phonology, morphology, syntax and lexicon; the most commonly noticed is the gorgia toscana, a consonant-weakening rule widespread in Tuscany in which the voiceless plosive phonemes /k/, /t/, /p/ are pronounced between vowels as fricatives [h], [θ], [ɸ] respectively.
Evidence: Florentine, and Tuscan more generally, can be distinguished from Standard Italian by differences in numerous features at all levels: phonology, morphology, syntax and lexicon. Perhaps the difference most noticed by Italians and foreigners alike is known as the gorgia toscana (literally 'Tuscan throat'), a consonant-weakening rule widespread in Tuscany in which the voiceless plosive phonemes /k/, /t/, /p/ are pronounced between vowels as fricatives [h], [θ], [ɸ] respectively.