Ore image classification based on small deep learning model: Evaluation and optimization of model depth, model structure and data size

•Developing more suitable small deep learning model for ore image classification.•Evaluating the gas-coal image classification performance of small deep learning models with different depths.•Optimizing the convergence speed and classification accuracy of small deep learning classification models by adding BN layer.•Evaluating the gas-coal image classification performance of small deep learning models under different dataset sizes.