Bill Kung of Ultimate Diamond: “Cause & Effect”

Cause & Effect — The biggest lesson I’ve learned and have taught the family is that every business decision has a cause and effect. It’s very important to notice what we’re doing, and the effect it has on the business. Seems obvious, but many businesses care about survival, instead of scale. Without cause and effect, your business […]

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Cause & Effect — The biggest lesson I’ve learned and have taught the family is that every business decision has a cause and effect. It’s very important to notice what we’re doing, and the effect it has on the business. Seems obvious, but many businesses care about survival, instead of scale. Without cause and effect, your business may survive but it certainly won’t scale.


As a part of our series about 5 Things You Need To Run A Highly Successful Family Business, I had the pleasure of interviewing Bill Kung, 2nd Generation Owner of Ultimate Diamond.

Bill is the second-generation owner of Ultimate Diamond, the oldest jeweler in NYC’s famous Diamond District and diamond dealer to the world’s largest luxury retailers since 1959. With over 40 years in the jewelry industry, Bill runs the business with his wife of over thirty years, two sons and daughter. Through referrals and walk-ins only, Bill and his team at Ultimate Diamond have provided insider access to the world’s most ethical natural and lab diamonds, and now, with their soon-to-launch eCommerce site, consumers can have access to that same transparent, wholesale pricing and superior customer service.


Thank you so much for joining us in this interview series! Before we dive in, our readers would love to learn a bit more about you. Can you tell us a story about what brought you to this specific career path?

When I came onto 47th street, NYC’s famous Diamond District, I was 23 years old. When I saw my father work hard and do everything for the family, I didn’t want to let him down, so I joined the family jewelry business.

Can you tell us a bit about your family business and your role in it?

Family and minority-owned since 1959, Ultimate Diamond is the oldest wholesale-gone-retail storefront jeweler in NYC’s famous Diamond District. We prioritize transparent, lowest-markup pricing, superior customer service, and above all else — insider access to the world’s most ethical natural and lab diamonds. We are your jeweler’s jeweler, meaning we provide diamonds, stones, and custom pieces to the world’s largest luxury retailers. As owner, I oversee our wholesale and retail business as well as the efforts underway to take our business online with the upcoming launch of our eCommerce site.

Can you share the most interesting story that happened to you since you began this career?

When I first took over the family business, a customer came into the store asking us to help him string a set of pearls. The cost of this service was 6 dollars. No one on the block would entertain his request because he didn’t seem like a “wealthy” customer nor did he seem like he had the prospect of becoming a repeat buyer. I humbly took him in and my mother stringed the pearls. Fast-forward a decade later, and he has purchased millions of dollars of diamonds from Ultimate Diamond. Since then, I’ve played a key part in dealing with the world’s most interesting diamonds — diamonds that went on to be purchased by celebrities like Beyoncé and Melania Trump, to the world’s rarest stones, such as 50 million-dollars and 25 million-dollars vivid blue diamonds at Christie’s. The world’s most interesting diamonds have passed through my hands and were all deals I’ve helped facilitate.

Can you share a story about the funniest mistake you made when you were first starting? Can you tell us what lesson you learned from that?

At one of my first diamond auctions, I bid for a F color VS clarity stone, when it turned out to be D flawless instead. The careless mistake actually brought me better return than the original stone would have! It taught me that a mistake is always an opportunity to learn (at least you’re trying!) and sometimes it can turn out to be a happy accident.

What do you think makes your company stand out? Can you share a story?

Unlike other jewelers or third-party diamond companies, when you shop at Ultimate Diamond, you’re buying straight from the source, skipping traditional supply chain and retail markups. We’re truly disrupting the diamond industry by providing buyers with exclusive access to quality diamond jewelry at transparent, wholesale prices. Not only that, Ultimate Diamond brings clarity to the diamond industry by demystifying the Diamond District and sharing an honest, insider look at how the diamond world works. Unfortunately, that’s not always the case, especially on this block. But that’s why we stand out. Our long-term client relationships and 5-star reviews prove this!

Are you working on any exciting new projects now? How do you think that will help people?

After 60+ years, we’re taking our clear, transparent pricing and diamond business online with the launch of our eCommerce site. Soon you’ll be able to shop for the most ethical natural and lab diamonds, usually only found at prices in NYC’s Diamond District, from anywhere in the world. Our mission is to provide everyday consumers with direct access to the diamond source through our marketplace, and to help people feel confident in their jewelry purchases by making diamonds and diamond education accessible to all.

None of us are able to achieve success without some help along the way. Is there a particular person who you are grateful towards who helped get you to where you are? Can you share a story about that?

My wife, Roni. We have an incredible partnership where I innovate and bring the vision, and she makes it come to life. She ensures all our innovations are delivered for long-lasting business results. Without Roni, our family business would’ve collapsed a long time ago.

How have you used your success to bring goodness to the world?

The diamond industry isn’t transparent, and that’s what I want to change. Not only do we use ethical, conflict-free diamonds, but we have invested in lab-grown diamonds because it’s important to us that we offer more sustainable options. With our eCom launch, we plan to donate to an environmental charity, and are taking steps to be carbon-neutral.

Ok thank you for that. Let’s now pivot to the main parts of our interview. How do you define a family business? How is a family business different from a regular business?

A family business is different because there’s a level of unspoken trust and understanding when working together. For the client, they feel that level of personalized service and trust. Roni and I see our clients face-to-face every day. You’re not meeting with the corporation, you’re meeting with us personally.

In your opinion or experience, what are the unique advantages that family owned businesses have?

As a family business, we don’t lose sight of why we started and how we started: from the ground up. This helps us put ourselves into the shoes of our clients. We don’t want just one sale of one diamond. We’re looking to form relationships with our clients, and their friends and families, and their generations to come. That mindset only comes from a family business.

What are the unique drawbacks or blind spots that family owned businesses have?

Working with family is always difficult, and as we’ve grown, we’ve had to be strict with ourselves in setting up processes to ensure smooth, consistent operations. When it was just myself and Roni dealing diamonds, we both knew the steps we had to take to help customers. When we added five more Diamond Specialists to our team, and didn’t have that natural instinct to create processes, it became harder to scale.

What are some of the common mistakes you have seen family businesses make? What would you recommend to avoid those errors?

I’ve seen many family businesses prematurely release authority to the next generation. It’s imperative to spend significant time training, imparting teachings and co-operating your business with your next generation to ensure they are ready to take over the reins. I’ve seen many family businesses pass to the next generation and ultimately close within 1–2 years because the next generation wasn’t prepared to lead.

What advice would you give to other CEOs or founders of family businesses to help their employees to thrive?

It’s important to let your employers know that everyone on the team has equal opportunities, whether they are family members or not. If other team members feel there is any entitlement, favoring, or lack of opportunities, they will not thrive. For us, it’s simple: everyone on the team is “family” and has equal opportunities for growth, support, and success.

How do you define “Leadership”? Can you explain what you mean with a story or example?

Leadership is doing by example. Roni and I have been in the store every day for over 35 years leading by example, from the seemingly small details of placing jewelry in the showcase, to the big things like selling million dollar per carat stones.

Here is our main question. What are the “5 Things You Need To Run A Highly Successful Family Business”? Please share a story or example for each.

1. Dedication — I live this business. My life is this business and I’ve dedicated myself to perfecting my craft to ensure success. Your family needs to have that same level of dedication and to also understand why it is a part of their story.

2. Plain Old Hard Work — If you don’t put in the time, you won’t succeed. It’s simple. My wife and I have worked 7 days a week for the past 35+ years. Show up, do the work, and the results will come.

3. Working With the Team — If you don’t show the younger generation and employees who are a part of the ‘family’ how to do it and why it’s important, they won’t believe you. Results speak for themselves, and results span generations.

4. Face Hardships Head On — When I first entered the Diamond District as the only Asian American business owner on the block, the community grouped together to outbid me, so that I’d fail as a business by not having the right inventory. I used that as fuel to my fire and now I am the most respected diamond dealer on the block with the largest inventory on hand.

5. Cause & Effect — The biggest lesson I’ve learned and have taught the family is that every business decision has a cause and effect. It’s very important to notice what we’re doing, and the effect it has on the business. Seems obvious, but many businesses care about survival, instead of scale. Without cause and effect, your business may survive but it certainly won’t scale.

Can you please give us your favorite “Life Lesson Quote”? Can you share how that was relevant to you in your life?

Understanding that life is “borrowed time” has always been really important to me. I drowned when I was 15. The hospital said I was medically dead for a few seconds, and in those seconds, I had an experience where I saw the light, saw God, and he pushed me back to Earth. Whether you are religious or not, my point is that ever since then I have taken every risk I could because every day is borrowed time. I’m here today after that experience on borrowed time, and that reminds me every day that whatever I do, I do it fully and take risks. Ever since then, that mentality has brought me success. Every risk I’ve taken has been successful.

We are very blessed that some of the biggest names in Business, VC funding, Sports, and Entertainment read this column. Is there a person in the world, or in the US with whom you would love to have a private breakfast or lunch with, and why? He or she might just see this if we tag them 🙂

Elon Musk. Everything he does is not for money, but for the better of mankind. Everything he has touched has been successful. His intention to start out was, of course, to make money and survive, but as soon as he could, he paid attention to initiatives that would better mankind. His visions are ones that normal humans don’t have, don’t consider, or can’t even possibly fathom. He does it for mankind because he knows no one else is paving or pioneering the way for it.

You are a person of great influence. If you could inspire a movement that would bring the most amount of good to the most amount of people, what would that be? You never know what your idea can trigger. 🙂

Clean and renewable energy everywhere. For the planet.

How can our readers further follow your work online?

You can check us out at UltimateDiamond.com or follow us on Instagram @UltimateDiamondCo. You can also reach out to our Diamond Concierge, Danielle, by emailing her at [email protected] Danielle can answer any and all questions you might have about diamonds and diamond education. Let her know you saw this article on me and depending on the diamond piece you’re interested in, you will receive 50 dollars, 100 dollars, or 500 dollars off your purchase. We have engagement rings and diamond jewelry to suit all budgets.

Thank you so much for joining us. This was very inspirational.

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