The cause of this optical phenomenon is phase exsolution lamellar structure, The effect is visible when the lamellar separation is between; the lamellae are not necessarily parallel;
22.
Exsolution can be on a scale from microscopic to readily observable in hand-sample; perthitic texture forms when Na-rich feldspar exsolve in a K-rich host.
23.
The ulv�spinel component tends to oxidize to magnetite plus ilmenite during subsolidus cooling of the host rocks, and the ilmenite so produced may form apparent exsolution ( trellis type ) laminae in magnetite.
24.
The upper critical temperature lies at about 760 �C and the lower one at about 500 �C . O . S . Moltschanova was the first person who exactly described the definition of the exsolution.
25.
The two phases in bursaite unlike those in lillianite are two " Bbmm " phases that appear to be exsolution products of phase III, which is simply the synthetic analogue of lillianite.
26.
Myrmekite is a microscopic, vermicular ( worm-like ) intergrowth of quartz and sodium-rich plagioclase common in granite; myrmekite may form as alkali feldspar breaks down by exsolution and silicon is transported by fluids in cooling rocks.
27.
There he came upon the mineral intergrowth called myrmekite where its origin did not fit the usually accepted models as to either being formed by exsolution from primary K-feldspar or by Na-and Ca-metasomatism along the margins of primary K-feldspar.
