A white candle with a wide enough base to stand on its own, a mirror, rocks and some marbles can all be brought together to create an interesting table decoration. Place the candle in the middle of the mirror, and surround it with rocks. You'll need to leave openings between the rocks so that you can fill them in with marbles. The light from the candle will play off the marbles and the mirror to create a pretty effect.
A table decoration using rocks and marbles does not need to be complicated. Get a large glass bowl, and place a layer of rocks in the bottom of it. To enhance the effect, you can paint the rocks a solid color such as black or red. Fill in the rest of the bowl with a layer of marbles on top of the rocks. If you have a crystal bowl, that will work with the marbles to cause interesting reflections of light.
A fish bowl or a clear canister can be the vessel for your water and marbles table decoration. Avoid using a fish tank as that does not offer the same effect as a fish bowl. The round shape of the bowl can create distorted reflections of the marbles, which add to the look. Fill the vessel or bowl halfway with water, and put a bottom layer of rocks in. Pour in marbles until the water reaches the top of the vessel.
Glue marbles to rocks using all-purpose adhesive, and allow them to sit overnight. Do not completely cover the rocks with marbles. You can enhance the effect by first painting the rocks and then attaching the marbles. You can paint the rocks solid colors, or paint designs on them. Arrange your marble-studded rocks in an interesting pattern on a small mirror at the center of the table. You can add to this effect by placing a small, battery-powered LED light at the center of your arrangement and letting the light reflect off the marbles and the mirror.