古
=
十
+
口
:
Mnemonic symbol: at least on German maps, this character actually resembles a cloister.
Oh no! Gitta Giraffe (gu) found that the golden cross (十) broke off of the cloister (古) in the space station's living room (Ø3)! She skewers a mandarin (口) on top of the cloister so that she can skewer the broken off cross back on to fix it.
十
=
一
+
丨
:
Mnemonic symbol: a holy cross. Sherlock Holmes (sh-) is investigating a very strange thing he found in the kitchen of the space station (-2): A big pyramid made of ten (十) crosses (十), which are in turn made out of flutes (一) and dinosaur bones (丨).
medieval / Middle Ages / Chinese middle antiquity, 3rd to 9th centuries, including Sui and Tang Dynasties / Middle (of a language, e.g. Middle English) / used / second-hand