Item #52: Silver/ Argint

Argintul se formează în depozite hidrotermale venoase sau în cantități mici în zonele de oxidare ale minereurilor purtătoare de argint.

Culoare: alb-argintie, care se înnegrește

Urma: alb-argintie

Luciu: metalic

Clivaj: absent

Duritate: 10-11

Silver occures in hydrothermal veins or in the oxidating areas of silver-bearing ores.

Color: silver-white

Streak: silver-white, tarnishes quickly to a black colour

Luster: metallic

Cleavage: none

Hardness: 10-11

The photo can be used provided the source is acknowledged.

Items #48-50: Echinoid fossils

Three examples of echinoid fossils from my museum; the determination was done by me.

1. Heliophora sp. – from a Miocene standstone formation in Northern-Africa. This species is now excinct.

 

2. Scutella sp.  – Oligocene to Lower Miocene of the Mediterranean region.

 

3. Mepygurus depressus – Callovian, Middle Jurassic of Madagascar

The photos can be used provided the source is acknowledged.