IN BRIEF

     Sierra HealthCare
     to end SIIS contract
     
      CARSON CITY -- Sierra HealthCare Options has informed the State Industrial Insurance System that it will not treat injured workers after July 1.
      System General Manager Doug Dirks said Tuesday that Sierra exercised its 60-day option May 1 to terminate its contract with the state. The managed care organization is one of three companies in Nevada that provide health care services to injured workers. It treats about 25 percent of workers under state workers' compensation laws.
      Sierra officials were not immediately available for comment. Dirks said he suspects the company ended its contract because it wants to provide total workers' compensation services in July 1997. That month private companies will be allowed to compete with the state-run insurance system in handling workers' compensation cases. Now the system contracts with companies to handle medical aspects of injured workers' cases.
      Horizon CompCare and St. Mary's Preferred of Reno are the only other companies that provide health care services to injured workers.
     
     Casino Data
     revenue drops
     
      Casino Data Systems reported total revenues of $13.2 million for the quarter ended March 31, down 11 percent from $14.9 million in the prior year's first quarter.
      The Las Vegas company recorded a net loss for the quarter of $3.3 million, or 18 cents a share, compared with net income of $1.7 million, or 11 cents a share, in the 1996 first quarter.
      Revenues from systems and products sales were about $7.1 million for the quarter, compared with $10.3 million a year ago.
      Casino Data Systems makes a diversified line of high-technology products and services for the gaming industry.
     
     Mining company
     takes legal action
     
      Nevada Manhattan Mining Inc. has instructed its legal counsel to take appropriate action against Argus Resources Inc. and its president, Marlowe Harvey, for knowingly issuing false and misleading statements regarding the Manhattan Gold Mining Project in Nye County.
      During 1993, Harvey agreed with Nevada Manhattan and Argus that he could earn a joint venture interest in the claims by purchasing the promissory note and deed of trust on the property.
      However, Harvey failed to perform his 1993 contract, according to Nevada Manhattan. In order to protect its interest in the claims, Nevada Manhattan purchased the note and deed in its entirety during 1997.
     
     Newmont completes
     Santa Fe takeover
     
      DENVER -- Newmont Mining Corp. has completed its takeover of Santa Fe Pacific Gold Corp. to become the biggest gold producer in North America and the second-largest in the world.
      On Monday, the $2.1 billion stock swap was approved by both companies' shareholders. Regulators approved it in March.
      Albuquerque, N.M.-based Santa Fe had previously agreed to merge with San Francisco-based Homestake Mining Co. Newmont, however, countered several months ago with a richer, hostile bid.
      The new company will have about 6,100 employees, combined 1996 revenues of $1.11 billion and exploration operations in 29 countries, including a key operation in Nevada on some 2 million acres.
      Newmont's main operation is in Nevada, but the company also has joint ventures in Peru, Uzbekistan and Indonesia.
     
     Yields increase
     on Treasury notes
     
      WASHINGTON -- Yields on three-year Treasury notes rose in Tuesday's auction to the highest level in more than two years.
      The average yield was 6.438 percent, up from 5.997 percent at the last auction on Feb. 11. It was the highest rate since three-year notes sold for 7.34 percent on Feb. 7, 1995.
      The notes will carry a coupon interest rate of 6 3/8 percent with each $10,000 in face value selling for $9,983.10.
      A total of $17 billion in notes were sold out of bids totaling $35.4 billion.