P.P.f. Weymar kindly sent me a bottle with large crystals in a letter: “At the bottom of the bottle, where the reagents were poured out when washing dishes, green and yellow crystals formed; I am sending these crystals to you; perhaps they are interesting for your crystallo- chemical analysis". Crystals of different colors turned out to be of different sizes and different appearances. The yellow crystals are clearly lamellar; The thickness of the plates is almost half a centimeter, and their largest size exceeds two centimeters. The greenish crystals are presented in a more isometric form and are at least four times smaller in linear dimensions.
