Nkkua stone in your palm: a guide for beginner mineral collectors

An independent guide for beginner mineral collectors. We are not a publication, museum or shop, we do not appraise or buy finds, and we are not connected with the former website on this domain.

Reference

Reference

Here, in plain language, are the words that come up in any conversation about stones. The terms are split into three groups: what stones are made of, which properties are used to describe them, and what you need to know about searching and storage. The definitions are short and formula-free, yet enough to read textbooks with confidence and follow experienced collectors.

The word “cleavage” sounds intimidating at first, but once you see a stone split along smooth, flat planes, the term sticks with you for good.

— A thought in the margin

Minerals

Mineral
A natural substance with a definite chemical composition and crystal structure. Quartz, talc and diamond are examples of minerals.
Rock
A natural aggregate of one or more minerals. Granite is a familiar example of a rock in which grains of different minerals are visible to the naked eye.
Crystal
A solid with an orderly internal structure, which often shows on the outside as flat faces: cubes, columns, plates.
Aggregate
An intergrowth of many crystals or grains of one or several minerals. Crystal crusts, druses and granular masses are all aggregates.

Properties

Luster
The way a mineral's surface reflects light. Collectors speak of glassy, metallic, greasy, pearly or dull luster.
Streak
The color of a mineral's powder left on an unglazed porcelain streak plate. It is often more reliable than the color of the specimen itself.
Hardness
A mineral's ability to resist scratching. It is compared using the Mohs scale of 10 reference minerals, proposed in 1812: from talc (1) to diamond (10), with quartz at 7.
Cleavage
A mineral's tendency to split along smooth planes in particular directions. In some minerals it is distinct; in others it is almost absent.
Fracture
The kind of surface produced when a mineral breaks other than along its cleavage planes: uneven, granular, splintery or shell-like (conchoidal).

Searching and collecting

Gravel bar
A deposit of water-worn stones on a shore or in a riverbed. A convenient place for your first searches, if collecting is allowed there.
Spoil heap
A pile of waste rock left over from mining. Search old spoil heaps only where it is permitted and safe.
Label
A card kept with a specimen, showing its number, its name or a note of doubt, the place and date of the find, and the finder's name.
Specimen
A single stone or a piece of one, kept for study and given a number and a label.

Where these words come in handy

  • Guides

    How to set up your first collection: labels, boxes and a field log. The article catalog lives here too.

  • Questions

    Short answers about identifying a find, searching safely and storing specimens.

  • Sections

    Four topics: minerals and rocks, identifying finds, searching and the law, and your collection at home.

  • Collections

    Reading paths: first rock-hunting trips, stones with kids, and a collection on the shelf.

  • Questions

    Short answers about identifying a find, searching safely and storing specimens.

  • Guides

    How to set up your first collection: labels, boxes and a field log. The article catalog lives here too.

  • Sections

    Four topics: minerals and rocks, identifying finds, searching and the law, and your collection at home.

Sources

  • Introductory mineralogy textbooks and handbooks
  • Encyclopedia sources on the Mohs scale

This information is accurate as of the date the page was prepared. Rules for visiting a particular area can change, and they differ from country to country, so before you head out for stones, check them with whoever manages or owns the land.