1‘diamonds, rubies, and other gems’
jewel, precious stone, semi-precious stone, stone, solitaire, brilliant, baguette, cabochon
2‘the gem of the collection is the tyrannosaurus skeleton’
best, finest, pride, prize, treasure, glory, wonder, flower, pearl, jewel, the jewel in the crown, masterpiece, chef-d'œuvre, leading light, pick, choice, paragon, prime, cream, the crème de la crème, elite, elect
outstanding example, shining example, perfect example of its kind, model, epitome, archetype, ideal, exemplar, nonpareil, paradigm, embodiment, personification, quintessence, standard, prototype, apotheosis, acme
informal one in a million, the bee's knees, something else, the tops
We take a look at several popular, though confusing, punctuation marks.