Final answer:
A blue mineral with well-defined crystal faces likely grew in an unrestricted environment, which is a condition necessary for the orderly arrangement of atoms and development of natural crystal shapes, such as those seen in azurite, amethyst, and fluorite.(true)
Step-by-step explanation:
The statement that a blue mineral with natural crystal faces and a beautiful crystal form likely grew in an unrestricted environment is likely true.
Natural crystals develop their characteristic shapes by the ordered arrangement of ionic solids due to the regular geometric pattern of atoms or molecules in the internal structure of the mineral, and this process occurs optimally in open spaces where the crystals have enough room to grow without interference.
Examples of such minerals include azurite (Cu₃(CO₃)₂(OH)₂), amethyst (SiO₂ with iron ions), and fluorite (CaF₂), where the color of the minerals can be affected by the presence of trace metal ions in the crystal lattice.
For instance, pure fluorite is colorless, but the presence of other metal ions can lead to varied colors in the crystal. Similarly, the green color of emerald is due to the presence of Cr³+ ions substituting for Al³+ in the beryl crystal lattice.