COLOROBBIA liquid golds and lustres have dissolved metals as their essential component. They are intended for brush-application onto already fired and glazed ceramic objects. Before firing, the objects must be left to dry for a few hours in a warm, dust-free place.
Firing temperatures recommended by COLOROBBIA are:
- On Earthenware glazed ware: 690°C - 700°C, Orton cone 018
- On Stoneware and Porcelain Glazed ware: 750°C - 815°C, Orton cone 017 - 015
- Colorobbia liquid golds and lustres are ready-to-use and are generally of a gluey, dark brown liquid appearance.
- Use a smooth, soft brush for application.
- The pieces to be decorated must be well-cleaned and bone dry.
- Gold, platinum and some lustres like copper and bronze do not need to be diluted. The other lustres can be diluted with an appropriate thinner at more or less 10% addition. The Mother of Pearl Iris lustre needs to be diluted at 15% at least: It burns more easily than the others if applied in thick layers. Burnt MOP Iris results in a white powder and does not adhere. Precision scales are recommended when diluting in order to maintain the same fluidity and shade of colour.
- The brush must neither be too heavily-laden nor too little-laden, and the layer applied must be uniform and fine (single brush stroke). Too thick a layer causes burning or clouding during the firing.