Is inside sinter
sinter
ˈsɪntə/
noun
1.
GEOLOGY
a hard siliceous or calcareous deposit precipitated from mineral springs.
2.
solid material which has been sintered, especially a mixture of iron ore and other materials prepared for smelting.
"typical blast-furnace burdens are 80% sinter, 20% ore"
verb
1.
(with reference to a powdered material) coalesce into a solid or porous mass by means of heating (and usually also compression) without liquefaction.
"when the moisture is removed from the slurry the powder compact is sintered"