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The most successful model of comet dust presents comet particles asaggregates of submicron grains. It qualitatively explains the spectral andangular change in the comet brightness and polarization and is consistent withthe thermal infrared data and composition of the comet dust obtained {\it insitu} for comet 1P/Halley. However, it experiences some difficulties inproviding a quantitative fit to the observational data. Here we present a modelthat considers comet dust as a mixture of aggregates and compact particles. Themodel is based on the Giotto and Stardust mission findings that both aggregates(made mainly of organics, silicates, and carbon) and solid silicate particlesare present in the comet dust. We simulate aggregates as {\bf BallisticCluster-Cluster Aggregates (BCCA)} and compact particles as polydispersespheroids with some distribution of the aspect ratio. The particles follow apower-law size distribution with the power -3 that is close to the one obtainedfor comet dust {\it in situ}, at studies of the Stardust returned samples, andthe results of ground-based observations of comets. The model provides a goodfit to the angular polarization curve. It also reproduces the positive spectralgradient of polarization, red color of the dust, and {\bf low albedo. It alsohas the ratio of compact to fluffy particles close to the one found {\it insitu} for comet 1P/Halley} and the mass ratio of silicate to carbonaceousmaterials equal to unity that is in accordance with the elemental abundances ofHalley's dust found by Giotto mission.

Comet dust as a mixture of aggregates and solid particles: model consistent with ground-based and space-mission results