Composite particle and method of producing composite particle

A composite particle comprising

• an alumina particle comprising molybdenum (Mo) and
• an inorganic coating part provided on a surface of the alumina particle,
• wherein the alumina particle comprises mullite in a surface layer of the alumina particle;
• wherein the alumina particle has a thickness is 0.01 μm or more and 5 μm or less;
• wherein the alumina particle has a particle size is 0.1 μm or more and 500 μm or less;
• wherein the alumina particle has an aspect ratio of 2 or more and 500 or less;
• wherein a ratio of the height A of the peak of mullite to the height B on the (104) plane of α-alumina (R) is 0.02 or more;
• wherein the inorganic coating part is made of an oxide or metal having a particle form,
• and wherein a particle size of the oxide or metal having a particle form is 1 nm or more and 500 nm or less.