A review is made on the present status of researches on spectral absorptions of silver particles of atomic, molecular and colloidal dispersions. Atomically dispersed silver is stable only in solid matrices and gives color centers such as B-centers in alkali halides. Diatomic silver molecules have been identified spectroscopically in vapor phase, and their properties constitute the basis, of quantum-chemical deductions on existence and properties of polyatomic silver molecules which have not yet been identified experimentally. Extensive studies have been made on color tones of colloidal silver. The absorption peak of colloidal silver in visible region generally shifts toward longer wavelengths and eventually becomes broader with increasing size, deviation from spherical shape, degree of impurity and extent of aggregation of the particles as well as with increasing refractive index of surrounding media. Trials have also been made to study the photolysis of silver salts in terms of spectral absorptions of silver particles produced. Some of these studies including the author's are described briefly.