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We present results of our photometric measurements of three samples of particulate surfaces consisting of dielectric and metallic spheres at extremely small phase angles. Monolayers of the spheres show satisfactory coincidence with the results of Mie-theory calculations. In particular, no opposition effect of the monolayer was found at the phase angle range 0.008 – 1.6° in accordance with Mie theory prediction. On the other hand, thick layers of the spheres reveal the opposition effect at phase angles less than 0.8°. In the case of dielectric spheres the opposition spike is due to the coherent-backscattering effect; whereas, for iron particulate surfaces the main contributor is perhaps the shadow-hiding effect. Measured dependencies do not allow us to separate these effects. 1 Introduction The motivation of this study is an astrophysical problem: Photometric observations of Kuiper belt objects reveal a prominent brightness opposition spike that is very narrow [1]. These objects are observed at very small phase angles (< 2°) and to reproduce these conditions in a laboratory requires the use of very small angular apertures of the light source and the receiver. Using an old laboratory of our Institute, which had been exploited as an analog processor for Fourier transformation of large images, we have constructed a laboratory laser photometer to study extremely small phase angles; this setup provides measurements in the range 0.008 – 1.6° [2]. This instrument allows us to measure the scattering properties of structural analogs of the surfaces of Kuiper belt objects. First of all it allows studies of the opposition spike effect in a wide physical context. For example, we here compare phase dependencies of intensity for dielectric and metallic small spherical particles that form a monolayer and thick layer in order to study the opposition effect related to the shadowing and coherent backscatter enhancement.