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Growth defects in a natural Brazilian single-crystal of beryl have been studied by X-ray topography, optical microscopy and electron microprobe. The distribution and configuration of channels and dislocations are both very different from those previously observed in other crystals and can be correlated with a `horseshoe' growth in a pegmatic medium. This was confirmed by the analysis of inclusions which allowed us to estimate the limits of temperature and pressure ranges in the genetic medium.