Sinoite is rare mineral with the chemical formula Si₂N₂O. It was first found in 1905 in chondrite

Chondrite

Chondrites are stony meteorites that have not been modified due to melting or differentiation of the parent body. They formed when various types of dust and small grains that were present in the early solar system accreted to form primitive asteroids...

 meteorites and identified as a disntict mineral in 1965. Sinoite crystallizes upon meteorite impact as grains smaller than 0.2 mm surrounded by Fe-Ni alloys and the mineral enstatite

Enstatite

Enstatite is the magnesium endmember of the pyroxene silicate mineral series enstatite - ferrosilite . The magnesium rich members of the solid solution series are common rock-forming minerals found in igneous and metamorphic rocks...

. It in named after its SiNO composition and can be prepared in the laboratory as a silicon oxynitride

Silicon oxynitride

Silicon oxynitride is a ceramic material with the chemical formula SiOxNy. While in amorphous forms its composition can continuously vary between SiO2 and Si3N4 , the only known intermediate crystalline phase is Si2N2O...

 ceramic.
The crystalline structure of silicon oxynitride is built by SiN₃O tetrahedra connected through oxygen atoms along the c axis and through nitrogen atoms perpendicular to it. The strong covalent bonding of this structure results in high flexural strength

Flexural strength

Flexural strength, also known as modulus of rupture, bend strength, or fracture strength, a mechanical parameter for brittle material, is defined as a material's ability to resist deformation under load...

and resistance to heating and oxidation up to temperatures of about 1600 °C.