when not next to another consonant. Consonant length and gradation Consonants, including clusters, that occur after a stressed syllable can occur in multiple distinctive length types, or quantities. These are conventionally labelled quantity 1, 2 and 3 or Q1, Q2 and Q3 for short. The consonants of a word alternate in a process known as consonant gradation, where consonants appear in different quantities depending on the specific grammatical form. Normally, one of the possibilities is named the strong grade, while the other is named weak grade. The consonants of a weak grade are normally quantity 1 or 2, while the consonants of a strong grade are normally quantity 2 or 3. Quantity 1 includes any single consonant. It originates from Proto-Samic single consonants in the weak grade. Quantity 2 includes any combination of consonants (including two of the same) with a short consonant in the coda of the preceding syllable (in Eastern Finnmark, any combination of consonants preceded by a long vowel or diphthong). It originates from Proto-Samic single consonants in the strong grade, as well as combinations of two consonants in the weak grade. Quantity 3 includes any combination of consonants (including two of the same) with a long consonant in the coda of the preceding syllable (in Eastern Finnmark, any combination of consonants preceded by a short vowel or diphthong). It originates from Proto-Samic combinations of two consonants in the strong grade. Throughout this article and related articles, consonants that are part of different syllables are written with two consonant letters in IPA, while the lengthening of consonants in quantity 3 is indicated with an IPA length mark (). Not all consonants can occur in every quantity type. The following limitations exist: Single is restricted to quantity 1, and does not alternate. Postaspirated consonants do not occur after a stressed syllable, and thus do not have any quantity distinctions. Voiced stops and affricates only occur in quantity 3. In quantity 1, voiced stops are allophones of the corresponding voiceless stops. , and occur in quantity 2 and 3, but not in quantity 1. When a consonant can occur in all three quantities, quantity 3 is termed "overlong". In quantity 3, if the syllable coda consists of only , or , the additional length of this consonant is realised phonetically as an epenthetic vowel. This vowel assimilates to the quality of the surrounding vowels: Between two rounded vowels (but