Euhedral crystals are those crystals that have well-formed faces and sharp angles. They exhibit a regular and distinct geometrical shape due to their ideal internal structure. Examples of euhedral crystal habits include octahedral habits (e.g., diamonds and magnetite), dodecahedral habits (e.g., garnets and fluorite), and cubic habits (e.g., galena, halite, and iron pyrite). On the other hand, non-geometrical crystals do not have a regular shape. These crystals have characteristic habits that can help identify the mineral. Examples of non-geometrical crystal habits include prismatic habits (e.g., tourmaline and quartz), bladed habits (e.g., kyanite), banded habits (e.g., malachite), and botryoidal habits (e.g., hematite).