das Steinchen
small stone
A very small stone; the diminutive form of 'Stein' (stone).
Das Kind warf ein Steinchen ins Wasser und beobachtete die Ringe.
The child threw a small stone into the water and watched the ripples.

small stone / little gem
Loading your saved state.
small stone
A very small stone; the diminutive form of 'Stein' (stone).
Das Kind warf ein Steinchen ins Wasser und beobachtete die Ringe.
The child threw a small stone into the water and watched the ripples.

'Steinchen' (small stone/little gem) is the diminutive form of 'der Stein' (stone). The ending '-chen' makes the word neuter ('das') and expresses that something is small.
Mein kleiner Sohn sammelt am Strand bunte Steinchen.
My little son collects colorful small stones on the beach.
Context tells you whether a small stone or a decorative gemstone is meant. In connection with nature, paths, or shoes, it means an ordinary stone. In the context of jewelry, rings, or dresses, it means a small gemstone.
Ich habe ein lästiges Steinchen im Wanderschuh.
I have an annoying small stone in my hiking boot.
In the meaning of 'small stone', the word often appears in fixed phrases, for example 'ein Steinchen ins Wasser werfen' (to throw a small stone into the water) or 'ein Steinchen im Schuh haben' (to have a small stone in one's shoe).
Er saß am Seeufer und warf gedankenverloren Steinchen ins Wasser.
He sat on the lakeshore and absentmindedly threw small stones into the water.
stone
'der Stein' and 'das Steinchen' both refer to a solid piece of rock. 'Steinchen' is the diminutive form and means a very small stone. It can also sound affectionate or more precise when something really is small. In addition, 'Steinchen' can mean a small decorative stone or gem in jewelry. Learners may confuse the words because they belong to the same word family. For normal-sized or larger pieces, you say 'Stein'; for very small pieces or small decorative stones, 'Steinchen' fits better.

Im Bus findet Emma ein kleines Steinchen in ihrem Schuh.
On the bus, Emma finds a small stone in her shoe.
Auf dem Weg liegt ein großer Stein, über den fast jemand stolpert.
There is a large stone on the path that someone almost trips over.