How to identify Mookaite Jasper

To correctly identify Mookaite Jasper (Silica (SiO2)), check each of these features in order. Many rocks and minerals look alike, so cross-reference multiple properties before deciding.

Step-by-step identification

1. 1

   Color

   Overall color and any zoning or banding

   Varies widely, including shades of red (from deep maroon to brick red), yellow (mustard to golden), cream, white, purple, and brown. Often exhibits swirling patterns, bands, or splotches of these colors.

2. 2

   Luster

   How the surface reflects light: metallic, vitreous, dull

   Vitreous to waxy, sometimes dull on unpolished surfaces.

3. 3

   Texture

   Grain size and surface feel: coarse, fine, glassy

   Smooth, fine-grained, and dense. Can feel slightly waxy to the touch.

4. 4

   Crystal Form

   Shape of visible crystals or crystal faces

   Cryptocrystalline (microcrystalline aggregates), no visible individual crystals to the naked eye.

5. 5

   Cleavage

   How it breaks: flat cleavage planes vs irregular fracture

   None, exhibits conchoidal fracture.

6. 6

   Geological Environment

   The rock formation and setting where it occurs

   Found in weathered sedimentary deposits, specifically in the Mooka Creek area, associated with radiolarian chert beds within the Windalia Radiolarite formation.

Key Facts

Hardness

6.5-7 on the Mohs scale

Specific Gravity

2.58-2.62 g/cm³

Crystal System

Trigonal (cryptocrystalline aggregates)

Color

Red, yellow, purple, cream, brown (often variegated)

Luster

Vitreous to waxy

Transparency

Opaque to translucent

Fracture

Conchoidal

Cleavage

None

Composition

Silicon dioxide (SiO2) with various iron oxide/hydroxide impurities

Physical characteristics

• Crystal Habit: Massive, cryptocrystalline aggregates
• Cleavage Type: None
• Fracture Type: Conchoidal
• Tenacity: Brittle
• Luster Type: Vitreous to waxy

Explore Mookaite Jasper