Producing a fine mixed lithium transition metal phosphate, or a lithium titanate, comprises: (a) providing starting compounds of lithium transition metal phosphate or lithium titanate comprising e.g. a lithium source; (b) converting the starting compounds to a precursor mixture and/or precursor suspension, which is then optionally converted to a lithium transition metal phosphate or lithium titanate compound in the form of a suspension; and (c) recovering the lithium transition metal phosphate compound or lithium titanate compounds or the precursor mixture and/or precursor suspension. Producing a magnetic contamination-free fine mixed lithium transition metal phosphate, or a lithium titanate, comprises: (a) providing starting compounds of lithium transition metal phosphate or lithium titanate comprising a lithium source, a transition metal source and a phosphate source or lithium-, titanium- and oxygen-sources, where magnetic impurities and undissolved or non-suspended particles are separated from the source; (b) converting the starting compounds to a precursor mixture and/or precursor suspension, which is then optionally converted to a lithium transition metal phosphate or lithium titanate compound in the form of a suspension, where magnetic impurities and undissolved or non-suspended particles are separated from the suspension; and (c) recovering the lithium transition metal phosphate compound or lithium titanate compounds or the precursor mixture and/or precursor suspension, which is then thermally treated and then freed of magnetic impurities. An independent claim is included for the lithium transition metal phosphate or a lithium titanate compounds with less than 1 ppm of magnetic impurities obtained by the process.