The Pearl in the Ice by Cathryn Constable

Marina is about to be sent off to a school for young ladies. She has no desire to become a lady. She would much rather join her father, a naval Commander, on his ship the Neptune sailing off to Cadiz in Spain.

Before I continue with the plot just take a closer look at the names here - Marina - the place for a boat to dock. The ship is called the Neptune - he is the Roman god of the sea. If you look at my post labels you will see I have listed mermaids. Here are some descriptions of Marina's mother who disappeared some years ago:

"She called up a hazy vision of a pale face with large dark eyes. There was long dark hair, like trailing seaweed. Ropes of pearls that hung down over the stiff bodice of a green silk dress with lace ruffles, like white caps on waves. And two canes topped with mother-of-pearl leaning against her chair, which her mother used if she had to walk."

Speaking of descriptions here is another important one. On the day she is supposed to be heading to school, the day her father is supposed to be sailing to Spain, Marina jumps onto a different train - the one heading to Portsmouth. A strange woman joins Marina in the carriage. This lady, Miss Gaby Smith secretary to the First Sea Lord, seems to ask lots of questions and she even pays Marina's first class fare when the ticket collector arrives.

"A young woman in a neat blue-and-white striped suit with a white ruffled blouse had appeared in the corridor behind the guard. She wore a small straw hat perched on top of a pile of exuberant auburn hair. ... The woman clipped her consonants when she spoke. Where was she from? She was wearing very clean white crocheted gloves. Her skirt was so daringly short that it showed an inch of calf above the top of her neatly laced red boots."

Nothing sinister here? Perhaps. Just a tiny hint about her accent. But then Marina sees this mysterious woman again. She appears in Svengejar, the most northerly port in the Grand Duchy of Finnmark.  Before Marina can catch up to Miss Smith on the streets of this remote sea port, her father whisks her away back onto his ship, the Sea Witch. Marina's father was not travelling to Cadiz in Spain on the Neptune. Instead he tells Marina his mission is to repair a broken communications transmitter which is located in a remote inland part of Pechorin Island. The real purpose of this mission, however, will leave you breathless and the true identity of Miss Smith is sure to be a huge shock to all readers just as it is to Marina herself. What is going on here? And how is Marina's mother linked to this strange Northern Arctic military base? And what are we to make of the title - The Pearl in the Ice?

The Pearl in the Ice is a gripping story of heroism, betrayal and complex relationships. I often think about school libraries that like to use genre stickers. This book would need several - Adventure, Mystery, War, Spies, Thriller, Fantasy and Relationships.  

You can read the first ten pages on the Chicken House page. Click these quotes to read more plot details. 

Disturbing memories of her mute mother haunt Marina. Her mother has been gone for a long time, and she has been brought up by her father, the commander of a ship. Marina longs to be noticed by her father, but he has secrets of his own. Book Trust

I absolutely loved reading along with her journey and I loved that there was something going on underneath it all. You could feel that something wasn’t quite what it seemed but you couldn’t quite work out what it was … Daydreamers Thoughts

By basing her book half in reality and half not, Constable sets up some wonderful tension in her characters; the reader having to guess who is speaking the truth, and who not. Minerva Reads

It’s a story to make young readers believe anything is possible, and all the better for that. Books for Keeps

I would pair this book with The Seven Professors of the far North.

You might also enjoy Monster Odyssey - The eye of Neptune.