Mixed Feldspar and Quartz Pebbles
Silicon Dioxide (Quartz) and Potassium/Sodium Aluminosilicates (Feldspar variety) · Mineral Specimens / River Stones
Crystal System
Trigonal (Quartz) and Monoclinic/Triclinic (Feldspar); generally found as sub-rounded massive or granular pebbles.
Mineral Group
Silicates; Tectosilicates
Chemical Formula
SiO2 (Quartz) and (K,Na,Ca)(Al,Si)4O8 (Feldspar Group)
Formation Process
Igneous (primary formation in granite/pegmatites) followed by Sedimentary (weathering and erosion into pebbles).
About This Crystal
A collection of small, sub-angular to rounded pebbles. Colors include tan, grey, reddish-brown, and off-white. Appearances range from opaque to translucent with dull to earthy lusters due to weathering.
Physical Characteristics
Colors: Grey, Brown, Tan, White; Streak: White; Fracture: Conchoidal (Quartz) to Uneven (Feldspar); Specific Gravity: 2.5-2.7.
Optical Properties
Generally opaque to translucent; no significant optical phenomena like labradorescence visible in these weathered states.
Hardness & Durability
Origin Region
Global; common in alluvial deposits, riverbeds, and weathered igneous terrains.
Hardness & Durability
Mohs Hardness: 6 (Feldspar) to 7 (Quartz). Highly durable and resistant to chemical weathering.
Care & Maintenance
Wash with warm soapy water. These are robust specimens not sensitive to light or common household chemicals.
Rarity & Value
Common; very low market value, typically collected as garden decorative stones or river gravel.
Special Characteristics
None notable; basic rock-forming mineral aggregates showing typical mechanical weathering patterns.
Lore & History
Quartz has been used since prehistory for toolmaking; Feldspar is the most abundant mineral group in Earth's crust. Traditionally associated with grounding and earth energy.