Quenya 

sar

(small) stone

sar (sard-, as in pl. sardi) noun "(small) stone" (SAR). In Elessar, q.v. Since Tolkien let this name have a stem in -sarn- (genitive Ele[s]sarno, VT49:28), he may seem to have changed the stem-form of sar from sard- to sarn-.

* sardincë

noun. pebble
Quenya Group: Eldamo - fan inventions. Published by

Sindarin 

sarn

noun/adjective. (small) stone, pebble, stony (place), **with many stones, *[N.] stone as a material
Sindarin [RC/163; RC/327; RC/775; SA/sarn; UTI/Serni; VT42/11] Group: Eldamo. Published by

Beware, older languages below! The languages below were invented during Tolkien's earlier period and should be used with caution. Remember to never, ever mix words from different languages!

Early Quenya

hyelle

noun. pebble
Early Quenya [PE16/138; PE16/144] Group: Eldamo. Published by

tolot

noun. pebble, cobble-stone
Early Quenya [PE15/77] Group: Eldamo. Published by

* lalle

noun. pebble
Early Quenya [PME/050; QL/050] Group: Eldamo. Published by