Building rock tumblers is a project that can help children understand the geological process of the tumbling and smoothing of rocks in water bodies. A homemade rock tumbler is also a creative way of making polished rocks and stones for adornments. Read on
tumbled jasper - Jasper is another very popular tumbling rock. It is a semi-translucent to opaque material. It can be any color but is most often reds, earth tones and green. Most jaspers accept a very bright polish and polish easily for the beginner.
science Rock Cycle - When picking rocks for hardscapes use Metamorphic rock, especially with water (so it doesn't leach anything into water) also important to know what type of rockscape animals may have evolved in.