Sodalite (blue beads) and Clear Quartz (clear beads)

Sodalite: Hardness: 5.5-6 on Mohs scale. Color: Typically deep royal blue, often with white streaks or patches (calcite). Luster: Vitreous to greasy. Crystal structure: Isometric (rarely forms distinct crystals, usually massive). Cleavage: Distinct in six directions. Specific Gravity: 2.13-2.29. Clear Quartz: Hardness: 7 on Mohs scale. Color: Colorless and transparent. Luster: Vitreous. Crystal structure: Hexagonal (rhombohedral). Cleavage: None. Specific Gravity: 2.65.

Sodalite: It forms in igneous rocks that are rich in sodium and poor in silica, such as nepheline syenites and phonolites. It can also be found in metamorphic rocks. Its formation is typically associated with alkaline igneous intrusions. Geological age varies depending on the specific deposit. Clear Quartz: Forms in a wide range of geological environments, including igneous, metamorphic, and sedimentary rocks. It crystallizes from magma and hydrothermal solutions, and can also form through precipitation from silica-rich waters. It is one of the most abundant minerals in the Earth's crust, with ages spanning billions of years.

Sodalite: Primarily used as an ornamental stone and in jewelry (like the beads in the image). It is also carved into small sculptures and decorative objects. Clear Quartz: Widely used in jewelry due to its clarity and sparkle. It also has important industrial applications, including in electronics (oscillators, filters), optics (lenses, prisms), and as a raw material for glass and ceramics. It is sometimes used in construction aggregates.

Sodalite: It is named for its sodium content. Some sodalite specimens exhibit tenebrescence, meaning they can change color when exposed to light (often reversible). Clear Quartz: It is the second most abundant mineral in Earth's continental crust, after feldspar. Historically, clear quartz was believed to be permanently frozen ice. It is a piezoelectric mineral, meaning it can generate an electric charge under mechanical stress, and vice versa. This property makes it valuable in electronics.

Sodalite: In the field, look for its distinctive blue color, often interspersed with white veins or patches. It is commonly found in Canada (especially around Bancroft, Ontario), Brazil, Namibia, India, and the USA (Arkansas, Maine). Historically, large deposits were discovered in Greenland. Clear Quartz: Can be identified by its hardness (scratches glass), glassy luster, and lack of cleavage. Its common hexagonal crystal form (if present) is also a key identifier. It is found globally in almost all rock types. For collectors, well-formed, transparent crystals are highly sought after.