A crystal can be heavy.Logical formLearned from22 sentences. Layers can be constituted-of-or-filled-with crystals.Logical formLearned from22 sentences. Atoms can be in crystals.Logical formLearned from22 sentences. Defects can be in crystals.Logical formLearned from22 sentences. Crystals can be oriented.Logical formLearned from22 sentences. Crystals can be constituted-of-or-filled-with (calcium oxalate).Logical formLearned from21 sentences. A crystal can be colorless.Logical formLearned from21 sentences. (Ice crystals) can be in the atmosphere.Logical formLearned from21 sentences. Crystals can be sharp.Logical formLearned from21 sentences. A (crystal structure) can be three-dimensional.Logical formLearned from21 sentences. A crystal may undergo an orientation.Logical formLearned from21 sentences. A ballroom may light by (crystal chandeliers).Logical formLearned from21 sentences. A crystal can be clear.Logical formLearned from21 sentences. Crystals may undergo a development.Logical formLearned from21 sentences. Crystals can be nice.Logical formLearned from21 sentences.