Abstract:Basalt fiber is a kind of high-performance fiber manufactured by melting and drawing from basalt or rocks of similar composition. Fluctuation in the composition of natural rocks can cause difficulties in drawing and instability of fiber properties. This paper collected data on the chemical composition of 54 groups of raw rock and 114 groups of basalt fiber samples. The petrological, parameter index and other characteristics of the raw material needed for basalt fiber were summarized, and the optimal range of related parameter indexes of raw materials were proposed. The characteristics of raw rock which is suitable for the production of basalt fiber can be summarized as follows: from the perspective of petrology, basic rocks or intermediate rock with a SiO2 content of 53% to 57% are the optimal; the most suitable rock type is basalt or andesite; the most appropriate rock texture is intersertal texture, vitrophyric texture or hyaline texture. The influence of structure is indirect, mainly due to some adverse minerals which may be contained in fumarolic structure or amygdaloidal structure. From the perspective of mineral composition, hydrous minerals such as serpentine and zeolite will cause bubbles in the melt, which will affect the continuity of fiber preparation but will be conducive to the full melting of raw materials. High melting point minerals such as forsterite and magnetite will make it difficult for raw materials to melt completely, resulting in uneven melt and easy crystallization. From the perspective of parameter index, the optimal range of acidity coefficient (Mk) is 4.0 to 5.5. The viscosity coefficient (Mv) is 2.0 to 3.0. The ratio of silicon aluminum oxides to other oxides is 1.5~3.0. The molar fractions of oxides are n(RO) = 20% to 30%, n(RO2) = 57% to 70%, and n(R2O3) = 10% to 16% (R stands for cations).