my shiny, red Harley
It’s not uncommon to find minerals and even semi-precious crystals in stone used for floors and countertops– like this sample in marble.

It’s not uncommon to find minerals and even semi-precious crystals in stone used for floors and countertops– like this sample in marble. 

Frederick M. Hueston, PhD

This next story happened on a beautiful fall morning here in Florida. I had the urge for some wind therapy, so I hopped on the old Harley and decided to go for breakfast at a little coffee shop just outside of town.

I love these mornings, the sun coming up with a light fog in the air. This was going to be a good day, I thought, and hopefully no stone issues. I arrived at the old roadside café and no sooner got off the bike than my phone rang.

I took a deep breath and said to myself, Here we go again… “Stone Detective, here. How can I help you?”

I immediately recognized the voice that answered me – he was an old customer of mine, for whom I have solved many stone and tile installation mysteries. It was easy to recognize his voice since it was so high-pitched.

He sounded like he was breathing in helium all the time. I asked him what was up, and he told me he had a customer in a large condo he was renovating. They installed large format black marble tiles that developed these unusual spots or stains.

He asked if I could come take a look. He was about two hours away, and who was I to say no to a nice, paid bike ride south?

I finished my breakfast and ordered a cup of joe to go, and I was off. I arrived at the ferry – yes, I was headed for one of those multi-million dollar condos on an island that can only be accessed by ferry. 

The attendants guided me onto the boat and gave me a thumbs up.

Apparently, they liked my shiny, red Harley, or maybe they were bikers themselves. 

I pulled onto the slipper deck and went to the bow for the ride to the island.

It’s interesting the people you get to meet when you’re on a motorcycle, especially a trike like mine (see the photo). Before the ferry reached the shore, I must have had six people looking at my bike and asking questions.

Since they were all driving Bentleys, Mercedes and other luxury cars, I thought I would hand out my business card. You never know when folks will need a stone detective.  We docked on the island, and they all shook my hand and said have fun and be safe. I got on the bike, and I was off to meet my squeaky-voice client.

I was waiting for the elevator when out stepped my client, who had come down to get me.

We shook hands and he began to tell me that the owner was here and he was very picky. The owner was very upset about these strange spots, and I needed to proceed with caution when I talked with him.

Well, I’ve been there many times before with rich, picky clients. 

We arrived at the condo and there was this tall, almost seven-foot-tall man standing on the marble floor.

At first, I thought he might be a retired basketball player.

Later, I found out in fact he was not, but was a very wealthy businessman. He shook my hand and pointed to the floor, paved with large format black marble tiles. There were these gold spots about the size of a quarter on several of the tiles.

I got down on my knees, which, by the way, is getting harder and harder for me these days. As matter of fact, I am a member of the club, Sons of Arthritis, Ibuprofen Chapter. (LOL).  

I took out my field microscope and proceeded to examine the spots. 

I said, “Aha!” and looked up at my client and Lurch and said, “There’s gold in this here marble.” I said it like an old prospector character on one of those old Westerns who cackles, “There’s gold in them thar hills!”

From the awkward silence, and their blank expressions, I don’t think they got the cultural reference. Oops.

I explained that the spots weren’t really gold, but a form of Mica.

I told them it wasn’t a stain, and wasn’t a flaw, but was a rare, naturally-occurring mineral present in some stone.

I joked that if he wanted we could chip it out and cash it in at a pawn shop. They all laughed at that, thankfully. Mr. Lurch said it would make a good conversation starter, and he’d leave it the way it was.

 Another case solved. Now, back to the ferry and off to explore and find lunch. 

The Stone Detective is a fictional character created by Dr. Frederick M. Hueston, PhD, written to be entertaining and educational. Dr. Fred has written over 33 books on stone and tile installations, fabrication and restoration and also serves as an expert for many legal cases across the world. Send your email comments to him at