plagioclase

IPA: pɫˈeɪdʒiʌkɫeɪs

(mineralogy) Any of a group of aluminum silicate feldspathic minerals ranging in their ratio of calcium to sodium.

Examples of "plagioclase" in Sentences

(Feldspar) plagioclase, alkali-feldspar (H 6-6. 5)
I was staring a Ca-rich plagioclase and pyroxenes and ilmentite.
The minerals included in this group are orthoclase, microcline, and the plagioclase feldspars.
Of course plagioclase feldspars are also one of my favorites so I might be a little partial here.
These rocks are composed predominantly of the minerals plagioclase feldspar, amphibole, and pyroxene.
Most of the larger oxides and plagioclase are interstitial, having grown in the intercumulus pore spaces.
I found a moonstone (the plagioclase feldspar oligocase) almost as big as my fist, almost perfectly round.
All of these rock types are light in color because of the dominance of quartz, potassium and sodium feldspars, and plagioclase feldspar minerals (Figure 1).