mineral articles
What property describes a mineral's resistance to scratching or permanent deformation?
What is the most significant factor determining a mineral's hardness?
Which bond type results in exceptionally tough and hard structures like Diamond?
What typically causes an ionic crystal to cleave or break relatively easily when scratched?
Who developed the relative hardness scale commonly used by geologists today?
How is the Mohs scale accurately described regarding measurement type?
How does Graphite differ structurally from Diamond, resulting in a large difference in hardness?
What term describes hardness varying based on the direction the scratch test is applied?
What common object approximates a hardness of about 5.5 in field testing according to the provided chart?
Which mechanical property, independent of hardness, describes a mineral's resistance to breaking or crushing?
What geological classification is Yooperlite considered a specific, recognizable variety of?
What unique physical property elevates a nepheline syenite to the trade designation Yooperlite?
Which specific mineral is responsible for the bright orange or reddish glow observed in Yooperlite under UV light?
How does typical syenite primarily differ structurally from granite?
What specific type of syenite are Yooperlites classified as based on their mineral makeup?
According to the text, what kind of name is 'Yooperlite'?
What essential tool is required for the initial successful identification of Yooperlite in the field?
What color does the sodalite in Yooperlite typically flash when exposed to the correct UV light wavelength?
The presence of nepheline in Yooperlite suggests it formed from magmas relatively low in what component?
If a piece of Michigan nepheline syenite lacks fluorescent sodalite, what is it correctly identified as?