Specifically, what the scientists have found is that the iron adopts a crystalline structure, like a diamond, in the Earth's core.

BBC: Planet Earth

The first is a bulk removal, ion exchange process in which sodium is swapped for cesium or strontium within an inorganic, crystalline structure.

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Even though helium atoms are four times chunkier than hydrogen atoms, they are still small enough to find all the weak spots as they worm their way through the crystalline structure of solid steel several centimetres thick.

ECONOMIST: Tech.view

Methane hydrates are frozen water molecules that trap methane gas molecules in a crystalline, lattice-like structure known as a hydrate.

FORBES

After enhancing its reactivity, cardanol is chemically bonded with cellulose, which produces a durable thermo-plastic that is strong, heat resistant, water resistant and non-crystalline (short molding time), due to the bonded cardanol's unique molecular structure consisting of flexible and rigid parts.

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