The present invention relates to a blend of at least one boron source and at least one silicon source, wherein the blend comprises boron and silicon in a weight ratio boron to silicon within a range from about 5:100 to about 2:1, wherein silicon and boron are present in the blend in at least 25 wt %, and wherein the at least one boron source and the at least one silicon source are oxygen free except for inevitable amounts of contaminating oxygen, and wherein the blend is a mechanical blend of powders, and wherein particles in the powders have an average particle size less than 250 μm. The present invention relates further to a composition comprising the blend a substrate applied with the blend, a method for providing a brazed product, and uses.