Polished section of the Albești metagranite (Romania) showing blue quartz with color zoning.
Polished section of the Albești metagranite (Romania) showing blue quartz with color zoning.
Rio dos Remédios metarhyolite (Bahia, Brazil).
A grain of blue quartz from the Llano rhyolite (Texas, USA).
Polished section of the Llano rhyolite (Texas, USA). The next two photos show the same grain at various angles relative to the light source and its characteristic chatoyancy
Polished section of the Llano rhyolite (Texas, USA) showing its characteristic chatoyancy caused by submicron ilmenite inclusions.
Polished section of the Llano rhyolite (Texas, USA) showing its characteristic chatoyancy caused by submicron ilmenite inclusions.
Rio dos Remédios metarhyolite (Bahia, Brazil).
Rio dos Remédios metarhyolite (Bahia, Brazil).
Llano rhyolite (Texas, USA).
Pietrosu Bistriței porhyroid (Romania).
A blue quartz grain from a Rio dos Remédios metarhyolite (Bahia, Brazil) polished sample.
Polished section of the Albești metagranite (Romania) showing blue quartz with color zoning.
The polished section of the Albești metagranite (Romania) from the previous image, showing the color change in transmitted light.
Blue quartz from the Lainici-Păiuș quartzite (Romania) showing chatoyancy caused by rutile needles.
Polished section of the Rio dos Remédios alkali rhyolite (Bahia, Brazil).
Polished section of the Albești metagranite (Romania) showing blue quartz with color zoning.
Polished section of the Rio dos Remédios metarhyolite (Bahia, Brazil) showing blue quartz with color zoning.
Polished section of the Albești metagranite (Romania) showing blue quartz with color zoning.
Polished section of the Rio dos Remédios alkali rhyolite (Bahia, Brazil).
Polished section of the Albești metagranite (Romania) showing blue quartz with color zoning.
Polished sample of a Småland (Sweden) type granite.
Polished section of the Rio dos Remédios metarhyolite (Bahia, Brazil).
Microphotograph of a petrographic thin section showing exsolved rutile needles in the blue quart from the Milbank granite (South Dakota, USA).
Polished section of the Rio dos Remédios metarhyolite (Bahia, Brazil) showing a blue quartz grain with multiple color zones.
Polished section of the Rio dos Remédios metarhyolite (Bahia, Brazil).
Polished section of the Rio dos Remédios metarhyolite (Bahia, Brazil) showing blue quartz with two types of color zoning.
Polished section of the Milbank granite (South Dakota, USA) showing blue qaurtz with characteristic chatoyancy caused by exolved rutile needles.
Polished section of the Albești metagranite (Romania).
The polished section of the Albești metagranite (Romania) from the previous image, showing the color change in transmitted light.
Polished section of the Llano rhyolite (Texas, USA) showing a blue quartz grain with a color zoning shaped by the magmatic corrosion gulfs, and chatoyancy,
Polished section of the Llano rhyolite (Texas, USA) showing blue quartz with color zoning and chatoyancy.
Polished section of the Llano rhyolite (Texas, USA).
The polished section of the Llano rhyolite (Texas, USA) from the previous image, showing the color change in transmitted light.
Polished section of the Llano rhyolite (Texas, USA).
The polished section of the Llano rhyolite (Texas, USA) from the previous image, showing the color change in transmitted light.
Polished section of the Llano rhyolite (Texas, USA).
The polished section of the Llano rhyolite (Texas, USA) from the previous image, showing the color change in transmitted light.
Polished section of the Milbank granite (South Dakota, USA) showing blue qaurtz with characteristic chatoyancy caused by exolved rutile needles.
Polished section of the Milbank granite (South Dakota, USA) showing blue qaurtz with characteristic chatoyancy caused by exolved rutile needles.
Polished section of the Milbank granite (South Dakota, USA) showing blue qaurtz with characteristic chatoyancy caused by exolved rutile needles.
Polished section of the Milbank granite (South Dakota, USA) showing blue qaurtz with characteristic chatoyancy caused by exolved rutile needles.
Polished section of the Milbank granite (South Dakota, USA) showing blue qaurtz with characteristic chatoyancy caused by exolved rutile needles.
Polished section of the Pietrosu Bistriței porhyroid (Romania) showing blue quartz with color zoning.
Polished section of the Rio dos Remédios metarhyolite (Bahia, Brazil).
The polished section of the Rio dos Remédios metarhyolite (Bahia, Brazil) from the previous image, showing the color change in transmitted light.
Polished section of the Lalu granite (Romania).
Polished section of the Lalu granite (Romania).