Condensation processes, responsible for the main chemical differences between gas and solids in the galaxy, are the major mechanisms that control the cycle of dust from evolved stars to planetary systems. However, they are still poorly understood, mainly because thermodyna mics and kinetic models of nucleation or grain growth are lacking experimental data. To bridge this gap, we used a large volume three-phase AC plasma torch to obtain a full high temperature condensation sequence at elevated C/O ratio from a fluxed chondritic gas composition. We show that the crystallized suites of carbides, silicides, nitrides, sulfides, oxides and silicates and the bulk composition of the condensates are properly modelled by a kinetically inhib ited condensation scenario controlled by the gas flow. This validates for the first-time thermodynamic predictions of condensation sequence at high C/O ratio. On this basis and using appropriate optical properties, we also demonstrate the influence of pressure on the dust chemistry as well as the low probability of forming and detecting iron silicides in asymptotic giant branch (AGB) circumstellar environments as well as in our chondritic meteorites. Introduction Cosmic dust is of crucial importance for the evolution of our galaxy since it actively participates in the cycle of matter (gas and dust) from the interstellar medium (ISM) to stars and back from stars to the ISM 1 . Dust grains form principally in the gas outflowing from evolved stars and in the ejecta resulting from supernova (SN) explosions. Amongst progenitors, AGB stars are assumed to be the major contributor to the global cosmic dust budget 2 . During their late evolutionary stages, low-and intermediate-mass stars (< 8 M⨀) become red giants, increasing their radius by 2-3 orders of magnitude, and decreasing their surface temperature to 2000-3000 K. Further evolution of these stars (AGB phase) lead to significant mass loss of gaseous molecules and dust grains giving rise to circumstellar envelopes (CSE). Mass-loss rates of AGB stars, determined with various observational methods, are typically in the range of 10 -8 -10 -5 M⨀. year -1 but values as high as 10 -4 M⨀. year -1 have been found for more extreme objects 3 . Around cool stars, dust is formed in dense shells created by stellar pulsations or large-scale convective motions which propagate gas beyond the stellar surface 4 where gas cooling yields dust condensation. These dust grains are then accelerated away from the star by radiation pressure, dragging the gas away through friction, creating outflows with typical velocities of 5-30 km/s and eventually feeding the ISM 5 contributing thus to the material out of which our solar system formed. Dust forms from the matter already present when the stars formed and from the elements produced by the stars themselves. The dust composition changes as the star evolves and notably when the carbon to oxygen ratio changes during the episodic third dredge-up process 6 . Thermodynamic equilibrium calculations have provided convincing explanations of the marked chemical differentiation between oxygen-rich and carbon-rich AGB stars based on the high bond energy of carbon (i.e., 1077 kJ.mol -1 ≈ 11.1eV 7 ) and that CO is a very stable gaseous molecule at relatively high temperatures. Consequently, the dust chemistry in the inner CSE of AGB stars, R =1-10R * where R * is the stellar radius, is primarily controlled by the carbon-tooxygen ratio. When C/O ≤1 (O-rich stars), all carbon is bound in the CO molecule and the oxygen in excess participates to oxygen-rich dust formation 8 . In contrast, when C/O ≥1 (C-rich stars) carbon is in excess while all the oxygen is bound in CO and hydrocarbons molecules and carbon-rich grains are formed 9,10 . While the C/O ratio likely explains the fundame nta l