die Wertsache
valuable
An item of high material or personal value, such as jewelry, cash, or important documents. Usually used in the plural.
Bitte schließen Sie Ihre Wertsachen im Hotelsafe ein.
Please lock your valuables in the hotel safe.

valuable
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valuable
An item of high material or personal value, such as jewelry, cash, or important documents. Usually used in the plural.
Bitte schließen Sie Ihre Wertsachen im Hotelsafe ein.
Please lock your valuables in the hotel safe.

This word is a compound of 'Wert' (value) and 'Sache' (thing). So it literally means 'a thing that has value.'
Eine alte Münze kann eine wertvolle Wertsache sein.
An old coin can be a valuable item.
The word 'Wertsache' (valuable item) is almost always used in the plural, 'Wertsachen' (valuables). People rarely talk about just one individual valuable object this way; instead, they group several together.
Vergessen Sie nicht, Ihre Wertsachen aus dem Auto zu nehmen.
Don't forget to take your valuables out of the car.
Typical verbs in connection with 'Wertsachen' (valuables) are 'sicher aufbewahren' (to keep safe), 'einschließen' (to lock away), or 'versichern' (to insure). Valuables often include jewelry, cash, laptops, or important papers.
Es ist ratsam, seine Wertsachen gegen Diebstahl zu versichern.
It is advisable to insure your valuables against theft.
treasure / preciousness
'Wertsachen' and 'Kostbarkeiten' both refer to valuable objects. Because of this, they can easily be confused. 'Wertsachen' is the practical word for things you want to protect or not lose, for example money, jewelry, or documents. You often hear it in hotels, at swimming pools, or while traveling. 'Kostbarkeiten' sounds more special and often somewhat more elevated. It is more suitable for very rare, expensive, or beautiful objects, for example in a museum or in a collection. In short: 'Wertsachen' are valuable things in everyday life, while 'Kostbarkeiten' seem especially valuable or rare.

Bitte lassen Sie keine Wertsachen im Auto liegen.
Please do not leave any valuables in the car.
Im Museum werden alte Kostbarkeiten aus Gold und Silber gezeigt.
The museum displays old treasures made of gold and silver.