Not a diamond; appears to be cobalt blue glass or rough slag/mineral fragment
Not a diamond; appears to be cobalt blue glass or rough slag/mineral fragment · Rough, unpolished, irregular fragment
Not applicable (Rough/Uncut) Cut
Carat
Estimated 15-25 carats equivalent volume
Color
Deep vivid cobalt blue
Clarity
Semi-transparent with internal bubbles/flow lines indicative of glass
Shape
Rough, unpolished, irregular fragment
Overall Assessment
The specimen displayed is a rough piece of cobalt blue glass featuring conchoidal fracture patterns and internal characteristics typical of glass rather than any gemstone or diamond.
Cut Quality
Not applicable (Rough/Uncut)
Brilliance
Low to moderate vitreous luster
Fire
None
Scintillation
Poor due to lack of facets
Proportions
Irregular raw chunk, no standard table or depth
Symmetry
Asymmetrical rough form
Polish
Raw, unpolished surfaces with conchoidal fractures
Fluorescence
None to inert
Inclusions
Gas bubbles and swirl marks typical of manufactured glass
Blemishes
Surface chips, flow lines, and uneven texture
Origin
Man-made glass or industrial waste/slag
Treatment Detection
Colored glass composition
Estimated Value
Nominal decorative or collector value (less than $10)
Certification Estimate
Not gradable by diamond/gemological grading labs as a diamond
Investment Potential
None
Similar Diamonds
None (this is not a diamond)
Setting Suggestions
Not suitable for fine jewelry setting
Care & Maintenance
Standard cleaning with mild soap and water
Interesting Facts
Cobalt blue glass is frequently mistaken by amateurs for rough sapphire or blue diamond due to its intense color.