Reference

Franconite, a mineral first discovered in 1984 at the Francon quarry in Montreal, Quebec, Canada, is a hydrated sodium niobium oxide with the chemical formula NaNb₂O₅(OH)·3H₂O. Its detailed composition includes approximately 49.17% niobium (Nb) making up 70.34% of its oxide form Nb₂O₅, 6.08% sodium (Na) as Na₂O, and 2.40% hydrogen (H) as part of its water content ( \text{H}_{2}\text{O} ) (source).

Composition:

• Molecular Weight: 755.74 g/mol
• Elements: Sodium (Na), Niobium (Nb), Oxygen (O), Hydrogen (H)
• Chemical Formula: NaNb₂O₅(OH)·3H₂O

Characteristics:

• Hardness: 4 on the Mohs scale
• Specific Gravity: 2.72
• Crystal System: Monoclinic
• Appearance: Typically occurs as white 150-micron globules on other minerals such as weloganite, calcite, and quartz.

Significance:

Franconite is significant not only for its unique composition and structure but also for its locality of discovery. The Francon quarry, where franconite was first identified, is one of the most mineralogically prolific sites in Canada, second only to Mont Saint-Hilaire. This quarry has yielded multiple new mineral species, showcasing the geological diversity and mineral richness of the area (source).

The discovery of franconite highlighted the geological and mineralogical importance of the Francon quarry, emphasizing its value in scientific studies of niobium oxides. The quarry's extensive number of new mineral species discoveries make it an essential site for mineralogists and geologists.

For further reading, you can refer to more in-depth information and studies available at various mineral databases such as Mindat and Webmineral:

• Mindat
• Webmineral