This chapter aims to present a chemical and mineralogical classification of silicate agrominerals (ASi) and their potential for soil fertility management and plant nutrition. Derived from silicate rocks and some silicate materials from industrial processes, ASi are composed of more than 50% silicate minerals and are rich in bases, calcium, magnesium, and potassium. These mineral sources are designed for regional use and have direct effects on nutrient availability, increased soil pH, and the formation of functional neoformed minerals. Additionally, indirect effects include inorganic carbon sequestration, organic matter stabilization, and increased nutrient use efficiency compared to highly concentrated and soluble sources. This chapter proposes a chemical classification of silicate agrominerals into eight classes: magnesium-bearing (ASiMg), calcium-bearing (ASiCa), potassium-bearing (ASiK), calcium-magnesium-bearing (ASiCaMg), magnesium-calcium-potassium-bearing (ASiMgCaK), calcium-magnesium-potassium-bearing (ASiCaMgK), potassium-magnesium-calcium-bearing (ASiKMgCa), and potassium-calcium-magnesium-bearing (ASiKCaMg). This classification enables the differentiation of potential short-, medium-, and long-term effects, which are directly related to the reactivity of the minerals present in these sources. Although ASi represents one of the most abundant potential sources of agrominerals, systematic research on it has only gained momentum in the past 25 years. The development of these products has markedly influenced tropical agricultural soils, which tend to be more responsive to their application. Further research is required to establish practical application guidelines and management strategies tailored to these region-specific mineral products.