Mineraloids and their features 

A mineraloid is a naturally occurring mineral-like substance that does not demonstrate crystallinity. Mineraloids are amorph.

Opal with Manganese Dentrites

Eskişehir, Türkiye

Obsidian

Jet

A hard gem-quality hydrocarbon 

From Erzurum, Türkiye

Menilite

Opaline concretions found in marls, gypsums and shales. Sometimes considered a variety of opal but probably impure and really just young Flint nodules which haven’t recrystallised to quartz yet; thus really a rock rather than a mineral.


Limonite

Chemical Formula : FeO(OH)·nH2O

Mohs Scale : 4 - 5.5

                                 Opal

Green Opal

Chemical Formula : SiO2·nH2O (hydrated silica)

Mohs Scale : 5.5 - 6 


Limonite

From Egypt


Obsidian


Limonite

From Egypt

Opal

Shungite

Shungite is a black mineraloid made of up to 99 percent carbon. Mohs scale of shungite is around 3.5 -4 


Obsidian


Limonite

Chrysocolla 

Menilite

Opal