ray diffraction diagram and by a water content of from 22 to 24 medicinal products containing the same which are useful in the treatment of osteoporosis and arthrosis application_number US 22838108 A description the applicant has now found that strontium ranelate can be obtained in a well defined crystalline form which is perfectly reproducible and which by virtue of that fact has valuable characteristics in terms of filtration and ease of formulation more specifically the present invention relates to the alpha crystalline form of strontium ranelate characterised by a water content of from 22 to 24 and by the following powder x ray diffraction diagram measured using a panalytical x 39 pert pro diffractometer together with an x 39 celerator detector and expressed in terms of ray position bragg 39 s angle 2 theta expressed in degrees ray height expressed in counts ray area expressed in counts u00d7 degrees ray width at half height u201c fwhm u201d expressed in degrees and interplanar distance d expressed in u00e5 the invention relates also to a process for the preparation of the alpha crystalline form of strontium ranelate characterised in that a solution of strontium ranelate or a hydrate thereof in water is heated to reflux and then cooled until crystallisation is complete and the product is collected by filtration in the preparation process according to the invention it is possible to use strontium ranelate or a hydrate thereof obtained by any process for example strontium ranelate octahydrate obtained by the preparation process described in the patent specification ep0415 850 an advantage of obtaining the said crystalline form is to allow especially rapid.