Crystalline silicates and processes for the production thereof are described. These crystalline silicates are of new crystalline structure, which, as determined after calcination in the air at 550.degree. C., have a composition represented by the general formula (I): pM.sub.2/n O.Al.sub.2 O.sub.3.qSiO.sub.2 (the symbols are as defined in the appended claims) and give a X-ray diffraction pattern as shown in Table 2. They are superior in heat resistance and acid resistance, and can be used as catalysts for the conversion of various organic compounds, absorbents, or as catalysts for various reactions. They are produced by reacting an aqueous mixture comprising (a) a silica source, (b) an alumina source, (c) an alkali metal and/or alkaline earth metal source, and monoethanolamine at a temperature of 100.degree. to 300.degree. C. until the desired crystalline silicates are formed. Although monoethanolamine does not remain in the crystalline silicates, it plays an important role in the formation of the desired crystalline structure in the course of the production thereof.