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It is the advance in methodology, together with conceptual progress that promotes experimentally-oriented scientific disciplines, as represented at the Bayerisches Geoinstitut. Technological developments are important because the institute also serves as a central national and international facility, i.e. it has to provide external users with access to advanced technologies in the entire field of experimental geochemistry and geophysics.

Whereas some of the methods used are relatively "standard" techniques of sample synthesis and characterization, which only have to be adapted to the specific requirements of the research at the Bayerisches Geoinstitut, many others are original contributions to the advance in experimental techniques. Only the latter will be described in this section.

Quo vadis, experimental geochemistry and geophysics methodology? The following directions are considered to be increasingly important for experimental geosciences in the coming years:

- increase in pressure-temperature range, improvement of pressure and temperature calibrations,

- increase in sample volume at high pressure and temperature,

- control and measurement of all pertinent intensive variables, in addition to pressure and temperature (such as oxygen fugacity and the activity of components),

- in-situ measurements at high pressures and/or high temperatures for the determination of material properties that cannot be quenched (e.g. elasticity, compressibility, viscosity, electrical conductivity, creep) and for studying unquenchable phase transitions,

- improving the spatial resolution and sensitivity of techniques for the structural and chemical characterization of experimental products that are typically heterogeneous, fine-grained and small in amount,

- determination of direction-dependent properties (such as diffusivity, interface structure, nucleation phenomena, deformation mechanisms) at both microscopic and mesoscopic levels,

- insights into the dynamics of the solid, glassy and molten states (very slow to fast chemical exchange reactions, spin dynamics, speciation).

The following contributions briefly describe advances in most of these fields, which have been triggered by pressing scientific needs. They have been achieved despite a notorious deficit in technical manpower but with the enthusiastic support of the existing small technical staff. Many of these advances are highly significant or even breakthroughs: experiments that seemed to be "impossible" in the past have become possible (although still difficult), difficult experiments have become more straightforward to perform and now can contribute information which is crucial for more reliable extrapolations to the Earth's interior.