Organic (Often Found By Beachcombers)

Chert (Jasper variation)

Microcrystalline Quartz (SiO2)

Chert (with Quartz vein)

Chert (Silicon Dioxide, SiO2)

Shale (sub-type: Carbonaceous Shale)

Lutaceous Sedimentary Rock

Chert (Smooth River Pebble)

Silicon Dioxide (SiO2)

Crushed Limestone

Calcite-rich Sedimentary Rock (CaCO3)

Chert (Jasper variation)

Chert (SiO2)

Chert (specifically Flint or Jasper variant)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Glauconitic Sandstone (Greensand)

Glauconitic Sandstone ((K, Na)(Fe3+, Al, Mg)2(Si, Al)4O10(OH)2)

Petrified Wood

Silicified wood (principally Silicon Dioxide, SiO2)

Chert (Green variety)

Microcrystalline Opaline/Quartz (SiO2)

Chert (Jasper/Iron-stained Quartzite)

Silicon Dioxide (SiO2)

Chert (Chert / Flint)

Silicon dioxide (SiO2) - Microcrystalline quartz

Petrified Wood

Silicified Wood (SiO2)

Chert (Brown variety / Common Jasper)

Microcrystalline Quartz (SiO2)

Chert Nodule (Flint)

Microcrystalline Quartz (SiO2)

Blue Agate (Tumbled and Dyed)

Silicon Dioxide (SiO2) with likely organic dyes

Amber

Succinite (specifically for Baltic amber; fossilized tree resin)

Chert (Flint)

Silicon Dioxide (SiO2)

Chert (Chert Pebble)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (Brown variety)

Silicon Dioxide (SiO2)

Glauconitic Sandstone (or Greensand)

Glauconitic Siliciclastic Rock (Containing (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)

Chert (Nodule/Pebble)

Chert (Silicon Dioxide, SiO2)

Pearl

Calcium carbonate (CaCO3) + organic conchiolin (Biogenic Mineral)

Chert (often called Flint in dark varieties)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood

Silicified Wood (primarily SiO2)

Fossil Coral (Rugose Coral Fragment)

Rugosa (extinct order of solitary and colonial corals)

Chert (specifically Pink/Tan Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Jasper (Green/Yellow Moss Jasper)

Silicon Dioxide (SiO2)

Jasper (Brown Iron-Rich Variety)

Silicon Dioxide (SiO2) with Fe2O3 (Iron Oxide/Crystalline Quartz)

Chert (Arrowhead/Artifact Fragment)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Banded Chert (or Flint)

Microcrystalline Quartz (SiO2)

Banded Chert (River Siltstone)

Microcrystalline Quartz (SiO2)

Chert (Nodule)

Chert (Silicon Dioxide, SiO2)

Chert (Iron-stained)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Grey/Black variety)

Chert (Silicon Dioxide, SiO2)

Jasper

Jasper (Silica-rich microcrystalline Quartz, SiO2 with Fe2O3 impurities)

Chert (specifically Gray/Blue Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Septarian Nodule (Thunder Egg)

Septarian Concretion (CaCO3 + CaMg(CO3)2 + SiO2)

Chert (Yellow Jasper/Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Ferruginous Sandstone (Ironstone)

Arenite with Iron-Oxide Cement (FeO(OH)·nH2O / Fe2O3)

Chert (often called Flint or Jasper)

Cryptocrystalline quartz (SiO2)