John Arthur Herbst

Our deepest sympathies to your family.

Dear Cindy and family
I counted it a priviledge to call John my friend. A few years ahead of me John was very kind to me in my early years as a young professor and facilitated my participation in all sorts of research and technology ventures. He was always full of novel ideas and high energy but with a calm demeanor. Then in the late 80s through his company we started a collaboration using modelling software I had developed which was very successful (and a lot of fun) for which I am eternally grateful. John was a real pioneer in the development of simulation and control technology in the minerals industry - his work on comminution still provides the definitive way to analyse such processes.
He was also just the nicest man to be around.
RIP John from your English friend,
Mark Cross
Emeritus Professor
Swansea University
Wales, UK

Heart felt condolences and pray his soul rest in peace.
He was an accomplished scientist, great teacher and kind human. I had the privilege to learn and work with him.

I was deeply saddened to hear about the passing of John Herbst.
John was probably the smartest and most creative and inspiring person I have ever met in my professional life. Every time we met, I came away full of new ideas and renewed energy. I travelled with John in so many countries in all continents, it was incredibly good and fruitful… For me he was a personal friend as much as a leader.
He offered me a unique opportunity back in the late 1980s, it was the main turning point in my entire professional life. Thanks to this opportunity, after that, I experienced 25 years of true professional happiness. John was probably the most influential person I ever met in my career.
I will never forget him. I admired him not only professionally, but also as a person. He was kind, caring about people open-minded, generous in spirit, and had a remarkable ability to think internationally and on a large scale.
His influence will stay with me forever.
Please accept my heartfelt condolences and sympathy to his wife Cindy and his children and grandkids.

My most sincere condolences to John’s family and friends. I have very good memories of working with him for about 4 years. In 1983, I was a Professor in Argentina and John offered me to come to the University of Utah as a Research Associate for his Comminution Center. Unfortunately, life led us to take different paths – both leaving the U of U in 1987. John was very intelligent, funny, witty, and always ready to listen to new ideas: a consummate entrepreneur. Rest in peace John. Felix Alba.

My sincere condolences on the loss of John Herbst. He was a dedicated mentor whose guidance truly shaped my professional career. Thinking of his family and loved ones during this painful time.

I will always remember John not only as a remarkable leader of long term but also as a kind and genuine person. Working under his guidance was a privilege that shaped my career and my outlook on life. He led with vision, integrity, and compassion—qualities that inspired everyone around. Though he is no longer with us, his legacy will continue to live on in the people and work he touched. May he rest in peace. John, 一路走好！我们永远怀念您！

We are so sorry to learn of the passing of your dad Kira! May he rest in eternal peace. Prayers and love to you and your family.

As a young engineer, I met John in 1991 in Salt Lake City, getting to know him and his tech startup Control International Inc. with my eyes wide open. John and his team taught me John's pioneering work, model-based digital control of mineral processes. John was very smart and he was also charming and very convincing ! What I learnt from John during those days opened up all of the opportunities I have had in my career since then. Thank you John for that. All my sympathies to his wife and family.

I’ve known John for more than half my life, and he’s been part of so many chapters of our family’s story. His humor, warmth, and love for his family left an imprint on all of us. I’ll always be grateful for the years we shared and the memories that will stay with me. My heart is with everyone who loved him and will miss him.

He was truly a great man....Thinking of you and your family

Cindy,
Jeff McKay here. It’s been forever since I saw you or John. He was one of the smartest men I’ve ever met. He had a big impact on a lot of people and the world of mining. My condolences at your loss. Hope you are doing fine.

Cindy and Nici,
We were sorry to hear of John's passing.
May this be a time to reflect on good memories with John.
May your entire family be blessed and comforted in this time of loss.

Dear Professor Herbst,
The path you opened in mineral processing modeling is so profound that we continue to walk upon it — growing in number and spirit along the way.
Your wisdom, dedication, and vision have become an everlasting light guiding generations to come.
Your contributions are immortal.

With deepest respect and gratitude,

Former student of Prof. Rajamani

Emrah Tuğcan Tuzcu, PhD

To the Herbst Family,
John was a great mentor. I can say that with all earnest eventhough I never took a class from him or studied under him. I say this from friendship. He took great interest in my career early on and was key to me making a decision to do research for industry. He was a good man and I can only imagine as a dad, grandfather, etc as well. I am sorry for your loss. Thanks for sharing him with the metallurgy world! God bless you.

I was deeply saddened to hear about the passing of my dear friend and professor, Dr. John A. Herbst. I was truly fortunate to have had the opportunity to work with him beginning in 1978, when we developed our Dynamic Grinding Model on a Pet Computer—known as Dynamill. Together, we later achieved one of our greatest milestones: cracking the Dynamic Flotation Model (Dynaflote) and creating its online version. After graduation, I continued to build upon our work, implementing a Dynamic Online Model of Thickening (Dynathick), all inspired and guided by his creative and visionary approach.

Dr. Herbst was an inspiring mentor whose encouragement, curiosity, and innovative spirit shaped much of my professional journey. We remained in touch over the years, continually exchanging new ideas and sharing our enthusiasm for advancing process modeling and optimization.

He played a pivotal role in helping me pursue my lifelong dream—working with real-time process historians and analytics to optimize industrial operations. His legacy continues to guide me as I integrate Artificial Intelligence and Digital Twin Plant Models to maximize metal production in the mineral processing industry. I will always be grateful for his mentorship, encouragement, and support, including during my recognition as an Antoine Gaudin Award recipient and as a member of the National Academy of Engineering.

His influence will remain with me forever.
Please accept my heartfelt condolences and deepest sympathy to his beloved wife Cindy, his children, and his grandchildren.

With respect and gratitude,
Dr. Osvaldo A. Bascur

So sorry for your loss. May god comfort and watch over you and your family. Take care ❤

So very sorry Cindy my heart hurts for you 💔

Dear Cindy and Family,
Sorry to hear of John's passing. John was a great friend who had an impact on many and will be missed by all. His many contributions to mineral processing technology are quite significant first at the University of Utah as a metallurgy faculty member and then department chair. It was our pleasure to know and enjoy John. Conversations with John were always interesting whether dealing with technology, politics, or religion. We always enjoyed the discussion. He will be missed. Now home, rest in peace with Jesus.
With Love and Comfort from The Lord,
Jan and Pat Miller

John was a brother-in-law to me, my sister Jackie Harwood, brothers Steve and Brad Gray for about 25 years. He married my sister, Kip (Dianne Kristine Gray Herbst) in December of 1962. He was like my other big brother. He was always someone to look up to and ask advice, and was highly respected. He was wise, kind, so intelligent, talented, and generous, among other things. He always had a smile on his face. Also, many people may not know, he was very musical and loved to sing and play guitar. When our families got together it was always a folk fest! He loved camping and cross country skiing. He also had been a member of the Wasatch Presbyterian Church. He worked very hard on his education and career. He graduated from Northwestern University and did his post graduate work (Masters and Phd) at the University of California, Berkeley. He and his young family (John Randal Herbst, Richard Todd Herbst, and Kristin Irene Herbst Stierli) traveled around the world when he had presentations to give (India, Sweden, China are a few). They lived in Illinois, California, Florida, Saskatchewan, and Germany, and Utah. He was very accomplished. Here is a link to his accomplishments: https://aimehq.org/what-we-do/awards/aime-frank-f-aplan-award/john-herbst
We loved John very much and will miss, and have really missed him from being in our lives. We loved his mom, Helen, and dad, Art, too! They were like our second parents and our children’s second set of grandparents! We know you’re with Jesus and are feeling his love and peace.

John will be missed dearly, he has been a true inspiration and a great mentor. He has touched so many careers/lives all around the globe - I feel privileged to have worked with him side by side, him being my supervisor's supervisor, late Dr. Rajamani.

Rest in peace John, your legacy will live on.
Cindy and the family, please accept my heartfelt condolences.

Dear Cindy,
John has been my closest and best friend since I came to the United States 45 years ago. Dr. John Herbst devoted his entire life to the education and scientific research in processing technology. His research achievements have made significant contributions to the processing industry . He is world renowned scientist and his students spread around the world. All those who spent any time with him will have memories which will bring a smile to their faces. Let's remember John not as someone who was wrenched from us too soon in a far off land, but as one who gave joy to our lives. Think not what we have lost but what we gained from knowing him. Yichang Lo