Ken Caminiti's baseball career coincided with lots of developments in the baseball card world.

His early major league days came during the so-called "junk wax era" because cards of the late 1980s and early 1990s were generally mass produced (and typically not very valuable).

Out of the age of stale gum and overprinted cardboard came developments that are still in use today: higher-end releases, serial-numbered inserts, flashy, shiny, chromium card stock, and autographs and game-used items featured on cards.

Click here to pre-order a copy of my upcoming book “Playing Through the Pain: Ken Caminiti and the Steroids Confession That Changed Baseball Forever.”

Here's a look at a few metal-themed items of Ken's in my collection that stand out to me (also check out Pt. 1, Pt. 2, Pt. 3 and Pt. 4).

1997 Donruss Preferred Precious Metals

While Topps was spending the 1990s making gold parallel versions of its cards, Donruss was making cards using actual metal.

Donruss Preferred Precious Metals parallel cards feature either silver, gold or platinum, and Ken’s card happens to include 1 gram of fine gold.

The card was limited to 100 copies. The scarcity and sharpness and fact that it was made using gold make this one of Ken’s most valuable cards. This card is so neat to see in hand.

1997 Pinnancle Mint

Pinnacle loved metal.

As if cans weren't enough (and they could have been) the company in 1997 rolled out a card-coin crossover that featured players in gold, silver and brass. Coins have been done before and since, but it's tough to find a product quite like Pinnacle Mint.

Ken's gold-plated coin is a neat find, and not all that easy to track down (they were inserted 1:48 packs).

1999 Metal Universe Precious Metal Gems

There might be no other baseball product as uniquely 1990s as Metal Universe.

The first years of the product (1996 and 1997) featured fire and space and fantasy themes, while 1998 Metal showed skylines and other quirky backgrounds.

1999 Metal Universe was more aligned with the product's name, featuring metallic-looking card backgrounds.

Precious Metal Gems parallels are numbered to only 50 copies and feature a rainbow shine. There's also a Gem Masters 1/1 parallel.