Gem boosters and free user ?

As many of you know, the rule in the gem system is "don't upgrade without boosters". It's a real rule. When we deal with Radiant gems, getting it level max without any boosters will crackle it 99,9% of the time.

But the necessary boosters are untradable and in cash shop only. Is there a way to play as a free-user or does it end when we reach u8 ?