The authoritative public forum
  for Metal Finishing since 1989
  

  -----

Fundamentals of Speculum

Respected sir,

I am a regular subscriber of your Metal finishing magazine. We are getting many enquiries for nickel-free plating for Gold and Silver.We knew about the copper-tin alloy plating as it can be used instead of nickel.Sir if you can provide me the technical formulation of the bath and the trouble-shooting through e-mail.

I would be keenly waiting for your prompt reply as soon as possible.

THANKING YOU.
Your's faithfully,

PRITESH.JAIN
BOMBAY [Maharashtra]
1998

---

1998

Dear Mr Pritesh Jain ,

The Copper - Tin process process you want is a proprietary process offered by Enthone - OMI , however from reports I have from users in the UK & elsewhere, it requires a lot of control .

A simpler approach might be to consider Bright Acid Copper , followed by a Palladium strike and then Gold . I have seen such a process in operation and it works .

Depending on the metals being plated you may need to consider a Cyanide Copper process prior to the Acid Copper .

As the Palladium & Gold processes are proprietary , you would need to contact one of the major precious metal plating suppliers .

Regards

John Tenison - Woods
- Victoria Australia

---

The Enthone process may require no more control than for other copper-tin processes- Speculum is a hard silvery-white alloy containing approximately 42 percent tin.

  
Tom Pullizzi
Falls Township, Pennsylvania