Thursday 2 April 2015


Both are varieties of Chalcedony.

Chalcedony mineral hardness -> 7 Mohs (Same as Quartz)

Quartz is a mineral composed of silicon & oxygen (SiO2).

Differnece is come from impurity amount. Agate has less, so it's translucent to semitransparent & jasper has more, so it is opaque.




If difficult to differentiate “Jaspagate” term is used when a specimen contains both jasper & agate.

Chalcedony is a composed of micro-crystalline quartz ( Micro means tiny, not seen with eyes ) / cryptocrystalline means that the quartz is in the form of crystals that are smaller than 30 microns in size (a micron is a unit of measure that is 1/1000th of a millimeter).

(Other microcrystalline quartz are bloodstone, carnelian & chrysoprase)

Macro-crystalline ( Macro means large, can be seen by the eye or a simple len) quartz refers to quartz with a crystalline structure.

These include clear quartz, smokey quartz, amethyst, rose quartz, citrine & ametrine, all of which are translucent or transparent.

Diaphaneity means “how easily light passes through a material”

Levels of diaphaneity
  1. Transparent (light & images pass through)
  2. Semi Transparent (images may appear distorted or foggy through the mineral)
  3. Translucent (light passes through)
  4. Opaque (no light passes through)

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