Pigotite (type locality) on granite matrix
Chapel Port, St. Levan, Cornwall, UK
 
Pigotite as resin-brown glassy sinter on granite matrix (stabilisized with acrylic resin). Good reference specimen, recovered in June 2019 from a sea cave. Chapel Porth is type locality for this rare, Mellite-related organic mineral, Al8(C12H10C20) • 27 H2O (cf. extraLapis No.57, 2019, p. 124-125). Samples were analyzed by EDX and Raman spectroscopy, ex Stefan Weiß collection