A phosphor comprising: an inorganic compound in which an A element, wherein A comprises one or two or more kinds of elements selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, and Yb, is solid solved in an inorganic crystal including at least a metal element M and a non-metal element X and being represented by M n X n+1, wherein n is a value in the range of 3≤n≤52, wherein the metal element M comprises at least Al (aluminum), Si (silicon), and if necessary, an L element, wherein the L element comprises a metal element other than Al and Si, and wherein the non-metal element X comprises at least N (nitrogen), and if necessary, O (oxygen), and if necessary, an Z element wherein the Z element comprises a non-metal element other than N and O, an inorganic crystal having a same crystal structure thereof, or an inorganic crystal comprising a solid solution of these crystals, wherein the inorganic crystal represented by M n X n+1 comprises an inorganic crystal represented by Si x Al m+2-x O 3-x N m+x wherein m=n-2, and 0<x≤3, wherein the inorganic crystal comprises a crystal in an orthorhombic crystal system and having a symmetry in a space group Cmcm, and lattice constants a1, b1 and c1 have values in ranges: a1 = 0.31 ± 0.05 nm; b1 = 1.87 ± 0.2 nm; and c1 = 0.275 x (n+1) ± 0.1 nm. an inorganic compound in which an A element, wherein A comprises one or two or more kinds of elements selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, and Yb, is solid solved in an inorganic crystal including at least a metal element M and a non-metal element X and being represented by M n X n+1, wherein n is a value in the range of 3≤n≤52, wherein the metal element M comprises at least Al (aluminum), Si (silicon), and if necessary, an L element, wherein the L element comprises a metal element other than Al and Si, and wherein the non-metal element X comprises at least N (nitrogen), and if necessary, O (oxygen), and if necessary, an Z element wherein the Z element comprises a non-metal element other than N and O, including at least a metal element M and a non-metal element X and being represented by M n X n+1, wherein n is a value in the range of 3≤n≤52, wherein the metal element M comprises at least Al (aluminum), Si (silicon), and if necessary, an L element, wherein the L element comprises a metal element other than Al and Si, and wherein the non-metal element X comprises at least N (nitrogen), and if necessary, O (oxygen), and if necessary, an Z element wherein the Z element comprises a non-metal element other than N and O, wherein n is a value in the range of 3≤n≤52, wherein the metal element M comprises at least Al (aluminum), Si (silicon), and if necessary, an L element, wherein the L element comprises a metal element other than Al and Si, and wherein the non-metal element X comprises at least N (nitrogen), and if necessary, O (oxygen), and if necessary, an Z element wherein the Z element comprises a non-metal element other than N and O, an inorganic crystal having a same crystal structure thereof, or an inorganic crystal comprising a solid solution of these crystals, wherein the inorganic crystal represented by M n X n+1 comprises an inorganic crystal represented by Si x Al m+2-x O 3-x N m+x wherein m=n-2, and 0<x≤3, wherein the inorganic crystal comprises a crystal in an orthorhombic crystal system and having a symmetry in a space group Cmcm, and lattice constants a1, b1 and c1 have values in ranges: a1 = 0.31 ± 0.05 nm; b1 = 1.87 ± 0.2 nm; and c1 = 0.275 x (n+1) ± 0.1 nm. a1 = 0.31 ± 0.05 nm; b1 = 1.87 ± 0.2 nm; and c1 = 0.275 x (n+1) ± 0.1 nm.