An adjective for “stone” in the Gnomish Lexicon of the 1910s appearing as an element in G. gôf·clochiol “stone-fruit” (GL/40), derived from G. cloch “a stone” (GL/26).
Gnomish
guin
adjective. own, held, possessed
guin
adjective. ready, fresh
guin
noun. *woman
guinir
noun. slave
guinog
noun. chattel
guinoth
noun. property
gwin
noun. woman, female
arn
noun. son
bo(n)
noun. son
clochiol
adjective. stone
gond
noun. stone
gwein
noun. *woman
nîr
noun. woman
An adjective appearing as G. guin “own, held, possessed” in the Gnomish Lexicon of the 1910s, above another entry G. guig “a piece of property”, with a brace indicating the two entries had been combined (GL/43). It was likely based on gui the past form of G. gôtha- “possess, have, hold” (GL/42).
Neo-Sindarin: For purposes of Neo-Sindarin, I would update this adjective to ᴺS. garnen “owned, held, possessed” as the passive participle of N. gar- “hold, have” from The Etymologies of the 1930s derived from the root ᴹ√GAR (Ety/GAR). Compare N. garn “property” from the same root.