I am struck by the number of commentators on British television whom I’ve noticed pronouncing diamond as ˈdaɪmənd rather than ˈdaɪəmənd (or the smoothed variants of the latter ˈdaəmənd, ˈdaːmənd).
Naturally enough, those of us with a Jersey accent in English pronounce diamond as daːmənd, so it has two syllables, like dgiamant in Jèrriais (the modernised spelling could just as well be dgamant – the i being a mere sign of the palatalised dg)
We know that the pronunciation of dgiamant has historically been disyllabic. The following alexandrine from a C19th poem demonstrates this (and aren’t we glad we never standardised spelling around gu for palatalised dg?):
(The caesura following the sixth syllable falls after “Guiaman” – therefore “Guiaman” must, according to versification rules, have had two syllables dʒamã for the poet – probably Jean Sullivan)