Nanjing Columbia Arts&Crafts Co., Ltd.

We are a leading manufacturer here in p. R. China of crystal engravable products to the corporate and awards industry, dealing specially in corporate crystal gifts and awards, optical glass blanks (engravable), crystal arts & crafts, engraved crystal and glass, pressed glass items, laser engraved crystal promotionals (3d image inside)

We are equipped with advanced facilities such as laser engraving machine, three-dimensional depicting, packing, vacuum platting, computer-controled carving, press, drilling machine, screen printing and so on. We exported our crystal products to Europe and America in the past six years.

The quality

1. The glass is transparent white and have no color tint.

2. There is no visible defect on the surfaces, verges and corners.

3. There is no bubbles, knots and other visible optical nonhomogenioses. (it means that pieces must be without any bubbles and inhomogenioses visible with the naked eye. )

4. Cleanness of the surfaces - 4 class.

5. The size of bevels - 0.3 +/--0.1mm x 450.

6. Roughness of the surface rz=0.05.

7. Quality of the surfaces - no more 5 rings per cm in the field distanced more 1mm from the edge. (check flatness by test flat glass. )

8. All surfaces must be polished. No visible scratches and mat areas.

9. Tolerance for all sizes +0.5/-1.5 mm.

10. Tolerance for the right and other angles +/- 0.12 degree. (in every case difference of the angle from the right angle must not be seen by the naked eye. )

11. No cut corners.