A kit for preparing a sample in an ion beam sample preparation device comprising a broad ion beam irradiating means disposed in a vacuum chamber, the kit comprising: a) a shield retention stage comprising: i) a first datum feature; ii) a second datum feature; iii) a shield retention means having at least a shield releasing position and a shield retaining position; b) a shield having at least a rigid planar portion, to be removeably, such as for observation in a microscope, and replaceably held in said shield retention stage, said shield further comprising: i) a third datum feature formed integrally with said shield, wherein said shield retention means in said shield retaining position urges said third datum feature to abut said first datum feature; ii) a fourth datum feature formed integrally with said shield, wherein said shield retention means in said shield retaining position urges said fourth datum feature to abut said second datum feature; iii) a sample surface for durably adhering a sample to the shield, iv) a first shielding surface to be disposed in the path of the ion beam and positioned to shield a portion of the sample from the ion beam directed at the sample when said shield is held in the shield retaining position of the shield retention means; a second shielding surface having a portion disposed in the path of a portion of the ion beam; a shield edge formed where the first shielding surface meets the sample surface; whereby the datum features on both the shield and the shield retention stage ensure that the shield may be retained in substantially the same position and orientation each time; characterized in that the sample surface has at least one recessed portion for the flowing of adhesive between the shield and the sample. a) a shield retention stage comprising: i) a first datum feature; ii) a second datum feature; iii) a shield retention means having at least a shield releasing position and a shield retaining position; i) a first datum feature; ii) a second datum feature; iii) a shield retention means having at least a shield releasing position and a shield retaining position; b) a shield having at least a rigid planar portion, to be removeably, such as for observation in a microscope, and replaceably held in said shield retention stage, said shield further comprising: i) a third datum feature formed integrally with said shield, wherein said shield retention means in said shield retaining position urges said third datum feature to abut said first datum feature; ii) a fourth datum feature formed integrally with said shield, wherein said shield retention means in said shield retaining position urges said fourth datum feature to abut said second datum feature; iii) a sample surface for durably adhering a sample to the shield, iv) a first shielding surface to be disposed in the path of the ion beam and positioned to shield a portion of the sample from the ion beam directed at the sample when said shield is held in the shield retaining position of the shield retention means; a second shielding surface having a portion disposed in the path of a portion of the ion beam; a shield edge formed where the first shielding surface meets the sample surface; whereby the datum features on both the shield and the shield retention stage ensure that the shield may be retained in substantially the same position and orientation each time; characterized in that the sample surface has at least one recessed portion for the flowing of adhesive between the shield and the sample. i) a third datum feature formed integrally with said shield, wherein said shield retention means in said shield retaining position urges said third datum feature to abut said first datum feature; ii) a fourth datum feature formed integrally with said shield, wherein said shield retention means in said shield retaining position urges said fourth datum feature to abut said second datum feature; iii) a sample surface for durably adhering a sample to the shield, iv) a first shielding surface to be disposed in the path of the ion beam and positioned to shield a portion of the sample from the ion beam directed at the sample when said shield is held in the shield retaining position of the shield retention means; a second shielding surface having a portion disposed in the path of a portion of the ion beam; a shield edge formed where the first shielding surface meets the sample surface; whereby the datum features on both the shield and the shield retention stage ensure that the shield may be retained in substantially the same position and orientation each time; characterized in that the sample surface has at least one recessed portion for the flowing of adhesive between the shield and the sample. a second shielding surface having a portion disposed in the path of a portion of the ion beam; a shield edge formed where the first shielding surface meets the sample surface; whereby the datum features on both the shield and the shield retention stage ensure that the shield may be retained in substantially the same position and orientation each time; characterized in that the sample surface has at least one recessed portion for the flowing of adhesive between the shield and the sample.