What is crystallise?

Some articles on crystallise, crystallises:

Floating Charge - Remedies - Crystallisation
... speaking, it is not possible to enforce a floating charge at all - the charge must first crystallise into a fixed charge ... In the absence of any special provisions in the relevant document, a floating charge crystallises either upon the appointment of a receiver or upon ... Ltd v Manila Rly Co that a charge should also crystallise upon the company ceasing to trade as a going concern ...

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