human organs, maybe? well, I don't know how much those cost. but I've also held plenty of expensive lab reagents, equipment. maybe an inverted leica microscope would be the most expensive, that'll set you back a few thousand bones

Keys

Probably a smartphone.

My daughters.

An apple from Whole Foods

I think it was a small milling machine spindle that was like 10 grand, or part of a boeing 747 worth about the same

I tried this on once - https://45n0pr1wpm3ox9mbl3x0rhco-wpengine.netdna-ssl.com/wp-content/uploads/fly-images/46309/Lion-necklace_High-jewelry-collection-2012_3-e1577991079821-9999x700.jpg - I don’t know how much it cost because it didn’t have a price on it (if you have to ask the price you can’t afford it) but it’s well into six figures. Although the lion is carved out of rutilated quartz, that single cushion cut yellow diamond hanging under the lion is 32 carats alone. It’s totally over the top and not my taste at all, but the skill and workmanship is exemplary and it’s a thing of rare beauty.

A Zeiss objective.

A plastic box with the liver of an organ donor.

I used to handle expensive-ass lab instruments all the time where I worked before, fancypants microscopes and mass spectrometers and shit like that, size of a breadbox and cost like 50 grand plus you sneeze on the lens or something and it's ruined ... some of them were easily over a million but those you couldn't exactly pick up...I wheeled those in, does that count?

Assuming keys to a house doesn't count... my chest that contains my coin collection

My dad's rolex watch. I forget the exact dollar amount but it's an antique rolex worth more than a brand new car.

I may have held something really expensive that I forgot about, it's been a long life and I have a terrible memory, but the most expensive thing I can think of is from a few years ago when I bought my custom PC for about $3000. I carried it so technically it was in my hands.