kiezels

Kiezels are small rounded stones formed by the weathering and erosion of larger rocks. They occur naturally in riverbeds, on beaches and shores, and in glacial outwash. The action of moving water, sand, and ice smooths and rounds the edges, giving the stones a characteristic polished appearance. The mineral composition of kiezels varies widely, leading to a range of colors from white and gray to red, brown or green.

In landscaping and horticulture, kiezels are used as decorative ground cover, in pathways, around plants, and for water features. They are also used for drainage layers in pots and raised beds. In aquariums and terrariums, their inertness depends on composition; quartz and glassy pebbles are largely inert, while limestone pebbles can slowly raise pH. Sizes used commonly range from about 4 mm to 60 mm; larger stones are sometimes classified as keien or cobbles.

Care and sourcing: kiezels are sold bagged or in bulk; it is advisable to rinse them before use to remove dust. When collecting from natural sites, observe local regulations and avoid protected or sensitive areas. Periodically clean outdoor installations to prevent algae growth, and rinse thoroughly if used in aquariums. Most kiezels require little maintenance beyond cleaning, and they do not decompose. Select locally sourced stones when possible to reduce transport impact and to ensure suitability for the intended use.