The path of transition from aragonite to podlesnoite is quite different from that of aragonite to ancylite (Fig.
(2002) Crystal structures of two ancylite modifications.
Relationship to other species: It is a member of the ancylite
group, specifically the La-dominant analogue of kozoite-(Nd).
(1965) The accessory minerals from Predazzo granite (North Italy), Part III (datolite, gadolinite, hellandite, ancylite
, synchisite, uraninite).
There were aegirine crystals with oddly clubbed ends; pale pink, blocky ancylite crystals; spiky balls of calcite; very complicated, water-clear crystals of an unknown mineral; tiny, resinous brown crystals of a second mineral showing a hexagonal pyramid termination, and pale brown sprays that were obviously astrophyllite.
Other studies later showed the ancylite to be calcioancylite-(Ce).
The syenite pegmatites contain calcium catapleiite, titanium-rich lavenite, lorenzenite, cesium-rich astrophyllite, kupletskite, pyrophanite, leucophanite, strontium-apatite, loparite, calcium-rich seidozerite, strontium-rich and zirconium-rich perrierite, brookite, landauite, murataite, polylithionite, brewsterite, chabazite, monazite, ancylite
, bertrandite, vlasovite, hambergite.
This ancylite always contains some Ca substituting for Sr, and La and Nd substituting for Ce.
It is also found in fissures in hydrothermally decomposed schist, associated with ancylite, anatase, fluorapatite and boulangerite.
Ancylite crystallized during the last stages of the growth of quartz crystals, and is associated with chlorite, apatite, titanite, calcite, fluorite and kainosite.
Kainosite-(Y) occurs at Puiva in two different parageneses: kainosite (I) is found as a cleft filling with chlorite and fluorapophyllite, and on terminal faces of quartz crystals, where it may be intergrown with ancylite; in these cases, pyrite occurs as a still later growth on the two rare-earth species.
(1975) The crystal structure of ancylite