He famously traded in rare, well known diamonds. Some of the more notable diamonds included the Queen of Holland diamond, the Premier Rose diamond, the Red Shield diamond and the Pumpkin diamond. The Premier Rose was sold in 1989 for $10 million dollars.
It was likely the most ever paid for a diamond at the time. It came from a 353.9-carat rough diamond he picked off a conveyor belt from a South African diamond mine. It was cut into three flawless diamonds, including the 137-carat pear-shaped Premier Rose.
To honor Goldberg, his estate has contributed a significant charitable gift to the Gemological Institute of America, establishing the William Goldberg Endowed Scholarship Fund. This gift will allow for the training of future generations of diamond and jewelry professionals. This gift brings the William Goldberg Diamond Corp.'s cumulative giving to the Institute to more than $350,000.