What diamonds, gold, and The Carob tree have in common.

800px-Arcosu07The carob tree is a landscape tree here in California, but in the Mediterranean region it grown as a food crop. Carob is mildly sweet and is used in powdered, chip, or syrup form as an ingredient in cakes and cookies, and in chocolate substitute. Since chocolate contains theobromine, which is poisonous to some mammals, and carob does not, it is used to make chocolate-flavored treats for dogs. The island of Malta has a liqueur made from carob, Zeppi’s Harruba. I would love to try this someday. 

The carob tree was known in Antiquity and was introduced very early in Greece and is possible indigenous to Crete. During St.John the Baptist’s sojourn in the desert he fed himself on the nourishing pods of the carob, along with locusts, and honey.

Ceratonia siliqua’s common name, Carob,  alludes to the Greek word “kerátion” literally meaning, a small horn. This is the shape of the carob pod which holds inside the carob seed, used as food. It’s this seed that shares it’s history with the weight used to measure gems, carat.

The seeds are remarkably uniform in both size and weight, varying within very definite limits. Ceratonia siliqua, the 800px-Ceratonia_siliqua_MHNT.BOT.2011.3.89scientific name of the carob tree, derives from the Greek kerátion, “fruit of the carob” (from keras “horn”), and Latin siliqua “pod, carob.” The term “carat”, the unit by which precious metal and stone weight is measured, is also derived from the Greek word keráti?n, alluding to an ancient practice of weighing gold and gemstones against the seeds of the carob tree by people in the Middle East. The system was eventually standardized, and one carat was fixed at 0.2 grams. 

In late Roman times, the pure gold coin known as the solidus weighed 24 carat seeds (about 4.5 grams). As a result, the carat also became a measure of purity for gold. Thus 24-carat gold means 100% pure, 12-carat gold means the alloy contains 50% gold. 


About Trey Pitsenberger

Trey is a nurseryman, author, and speaker.

03. June 2014 by Trey Pitsenberger
Categories: | Tags: , , | 5 comments

Comments (5)

  1. I want to read what you are reading for your sources. I am a soon to retire corporate training developer but my heart has always been with plants. I have a day dream of starting some sort of specialty plant propagation business with maybe some other aspects, like container design. I admire that you pursued your passion for your whole career and that you also write about it in the way that you do.

    Also, I am interested that you are in Garden Valley, CA. I have some friends there, Phyllis and Keith Little, and I have visited there. It is a beautiful place. Do you know them? Keith is also a musician, as is my husband, and that is how we met, years ago. They grow and sell produce at the farmers market.

    Best regards,
    Virginia Hamilton

    • Hi Virginia,
      Yes, I know The Littles! They come into the nursery now and then. Keith is big in bluegrass and plays around here often. Keep the dream alive. It has been an interesting trip in horticulture, with many ups and downs. The trade is changing and those who keep nimble and alert will always find their place. Best wishes.
      Trey

  2. Great post, fascinating information. I really enjoy expanding my knowledge of the plant world.

  3. Very interesting! I enjoyed reading this, it provided me with information that was interesting and easy to understand.