Anthropogenic (Man Made Industrial Deposit)

Amethyst

Amethyst (Silicon Dioxide, SiO2)

Pyrite-rich rock (likely pyrite-bearing schist)

Pyrite (FeS₂) in a foliated metamorphic matrix; exact host rock cannot be confirmed from the image

Galena (likely)

Galena, lead sulfide (PbS)

Chert with Limestone

Silicon Dioxide (SiO2) in Calcium Carbonate (CaCO3) Matrix

Polished yellow calcite pendant

Calcite (CaCO₃)

Radiating stibnite crystals

Stibnite (antimony sulfide, Sb₂S₃)

Rough ruby-bearing corundum (identification uncertain)

Corundum (Al₂O₃), possibly ruby; the image alone cannot confirm ruby or distinguish it from other red-purple minerals.

Rounded gray-brown pebble

Indeterminate; likely weathered quartz-rich sandstone or fine-grained volcanic rock

Basalt

Basalt (containing plagioclase, pyroxene, and olivine)

Chert (Flint)

Microcrystalline Quartz (SiO2)

Amethyst (Tumbled Cabinet Stone)

Silicon Dioxide (SiO2) with iron impurities

Metallic sulfide mineral specimen, likely pyrite

Pyrite (FeS₂), possibly a pyrite-rich sulfide aggregate

Chert or Jasper

Microcrystalline Quartz (SiO2)

Fossil Sea Urchin (Echinoid)

Echinoidea fossil (often replaced by silica or calcite)

Malaysian 50 Sen Coin

Coinage (specific alloy unknown without metallurgical analysis, but typically brass or bronze for this denomination and era)

Fossilized echinoid (sea urchin), likely a flint/chalk-associated test

Echinoid fossil; likely a regular echinoid such as Echinocidaris or related taxon, composed mainly of recrystallized calcite (CaCO₃)

Green Glass Cullet / Recycled Glass

Amorphous Silicon Dioxide (SiO2) with various metal oxides

Flint

SiO2 (Cryptocrystalline Quartz)

Chert (Nodule)

Chert (Alpha-Quartz, SiO2)

Beryl crystal in a dark mica-rich matrix

Beryl, Be₃Al₂Si₆O₁₈; likely associated with biotite or schist

Slag (Industrial Byproduct)

Ferrous/Non-ferrous Silicate

Slag (Industrial By-product)

Glassy silicate or metallic smelting residue

Malachite

Malachite, Cu₂CO₃(OH)₂; a banded botryoidal copper carbonate specimen

Polished orbicular jasper (likely ocean jasper)

Microcrystalline quartz (SiO₂) with iron-oxide and volcanic/mineral inclusions

Banded Agate

Silicon Dioxide (SiO2) - Variety of Chalcedony

Tumbled brecciated jasper

Brecciated jasper, microcrystalline quartz (SiO₂) with iron-oxide staining and varied silicate fragments

Tumbled chalcedony pendant (likely agate)

Chalcedony, microcrystalline quartz (SiO₂); the pale bands suggest agate

Amethyst Cluster

Quartz (SiO2 with iron impurities)

Chert (Flint / Quartz Nodule)

Microcrystalline Quartz (SiO2)

Chert (variations include Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Dyed Chalcedony (Agate)

Silicon Dioxide (SiO2) with artificial pigment

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Chert (Flint / Jasper)

Silicon Dioxide (SiO2)

Small rounded pebble, likely quartz-rich stone

Indeterminate from photograph; possibly microcrystalline quartz (SiO₂) or a weathered silicate pebble

Native copper (probable copper-rich mineral specimen)

Copper, Cu; possibly mixed with cuprite, malachite, and iron-oxide alteration minerals

Iron-stained quartz-rich rock, possibly quartzite or silicified breccia

Quartz (SiO₂)-dominant rock with iron-oxide minerals, chiefly hematite/goethite

Galena (lead sulfide)

Galena, PbS

Weathered iron-rich river pebble

Likely basalt or mafic rock with limonite/goethite staining

Natural freshwater pearls

Pearl (nacreous calcium carbonate; chiefly aragonite, CaCO₃)

Tumbled rose quartz

Quartz (SiO₂), pink variety

Polished jasper pebble

Jasper, an opaque microcrystalline variety of quartz (SiO₂), with possible iron-oxide and other mineral inclusions

Smoky Quartz

Smoky Quartz (Silicon Dioxide, SiO2)