ZMK-750 clasp blank from ZlSr 750-250 and ZlSr 585-415 alloys

ZMK-750 is a clasp blank model for jewelry. The nomenclature lists both ZlSr 750-250 and ZlSr 585-415, so this product retains both options and does not choose the material for the buyer.

What this item is

The index 750 in the model matches one of the grades but does not exclude the second option explicitly listed. The grade, fineness, and composition of a specific delivery should be confirmed in the invoice and certificate. The clasp geometry is determined by the drawing, not by the composition.

Composition and documents

• Grades: ZlSr 750-250 and ZlSr 585-415
• ZlSr 750-250: gold 75.0–75.5%; silver 24.5–25.5%
• ZlSr 585-415: gold 58.5–59.0%; silver — balance
• Supply document: TU 9641-824-05785324-2006

These are two-component gold-silver alloys. The numbers in the designation specify the nominal fractions of precious metals in thousandths; the actual range is confirmed by the batch quality certificate. The grades cannot be substituted for each other based on color alone: composition differences affect processing, joining with other parts, and the final fineness of the product.

Applications and technological role

• assembly of clasps for jewelry chains and bracelets according to mating dimensions;
• further adjustment and finishing of the clasp mechanism;
• serial or repair replacement when the model, selected grade, and attachment method match;

What to agree before ordering

Specify ZlSr 750-250 or ZlSr 585-415, attach the ZMK-750 drawing, and set dimensions, mass, connection sizes, completeness, clearances, and tolerances. Agree on the mounting method, surface condition, allowable heating, and packaging. The supplier must confirm in one document the model, selected alloy, TU, and batch number; otherwise, the execution remains ambiguous.

Safety and handling

Store blanks separately by grade and batch, protecting from contamination, moisture, and damage. When grinding, polishing, or soldering, use local exhaust ventilation, eye protection, and gloves. Collect dust, chips, and trimmings separately as precious metal material; select the heating mode according to the process sheet.