UPDATE 1-Zygo gets unsolicited offer from II-VI, shares jump

* Offer values Zygo at about $170 mln

* Offer of $10/shr represents premium of 35.5 pct

* Zygo shares jump 47 pct, II-VI falls about 3 pct

Jan 7 (Reuters) - Zygo Corp (ZIGO.O), which supplies optical metrology instruments, said it received an unsolicited $10 per share offer from II-VI Inc (IIVI.O), representing a 35.5 percent premium to the stock's Wednesday close.

Shares of Zygo surged as much as 47 percent to $10.87 Thursday morning, suggesting that investors are expecting a higher bid.

II-VI's cash-or-stock offer values Zygo at about $170 million, based on about 17 million shares outstanding as on Sept. 30, 2009.

Zygo plans to hire an independent financial advisor to evaluate the proposal, it said in a statement.

The company also said it is in the late stages of implementing a substantial reorganization of its business.

Last year, Zygo had ended an agreement with Electro Scientific Industries Inc (ESIO.O), which had offered about $173.5 million for the company.

Shares of Zygo were trading up 41 percent at $10.40 Thursday morning on Nasdaq. They touched $10.87 -- their highest since October 2008 -- earlier in the session.

II-VI shares touched a low of $31.57, before paring some losses to trade down about 3 percent at $31.85. (Reporting by Shrutika Verma in Bangalore; Editing by Aradhana Aravindan)