Hoploscaphites nicoletti Options

[Gene Kooper]

I've been enjoying the last week or so packing everything up after 16 years in one house...Sigh.

However, it's not all bad. I finally unearthed several boxes of ammonite fossils I hadn't seen for 15 years. Many, many years ago, I visited a friend in Bismark, ND who had discovered a great ammonite locale in north-central South Dakota. The most common ammonite that we found on that field trip was Hoploscaphites nicoletti.

Here are a few photos from the first box I opened up.

Front and back of several Hoploscaphites nicoletti specimens. The back side of the largest fossil was not completely mineralized on the inside so you can see the structure of the chambers and suture patterns. In one of the other boxes I have a large specimen on matrix where the inside is also hollow. It has some amazing structural features including the siphuncle tube that allowed the ammonite to pump air and water to and from the chambers to control buoyancy. I just need to figure out which box it's in.

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Front and back of three Hoploscaphites nicoletti pieces that show the ribs and color fairly well.
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If I ever retire, I hope to finally have the time to prep some of the larger clusters.

[Gene Kooper]

Oops, I knew I was forgetting something. The specimen with the open chambers is approx. 3-1/2" x 2-1/2" in size. The large piece in the other group is 2" x 3". From what I collected, Hoploscaphites nicoletti don't get much bigger than this. I have a large plate approx 1 foot in diameter containing a dozen iridencent specimens.

I think you are right swizz. These could be called ammolites because of the iridescent nacre. However, the nacre is very thin, so not like the thick nacre of some Placenticeras specimens. I have a few Hoploscaphites nebrascensis that have the deep ruby-red and bright green colors commonly associated with ammolites. They are 4" to 6" in diameter.

I haven't done any cleanup or prep on these. This is what they look like right out of the concretion. One of the interesting things is that the shell initially grows in a spiral and then has a straight section.