Ivory is a material that comes from the tusks and teeth of animals like elephants, mammoths, walruses, hippopotamuses, and narwhals. It has a smooth, solid, and creamy white appearance. But is ivory actually heavy or light? The weight of ivory depends on several factors. In this article, we’ll take an in-depth look at the density and weight of ivory compared to other materials to answer the question of whether ivory is truly heavy or light.
What is Ivory?
Ivory is a hard, white material that makes up the tusks and teeth of animals like elephants, mammoths, walruses, hippopotamuses, and narwhals. It consists mostly of dentine, which is a calcareous material similar to bone. Ivory also contains small amounts of proteins and minerals like calcium and magnesium.
The main source of ivory is elephant tusks. Elephant tusks are actually modified incisor teeth that grow throughout an elephant’s lifetime. Elephant tusks are composed of layers of dentine surrounded by a coating of enamel. The tusks grow spirally outwards in layers as the animal ages.
Other sources of ivory include the tusks of extinct woolly mammoths, the canine teeth of hippopotamuses, and the tusks of narwhals, which are actually a spiraled single tooth. Walrus tusks, consisting of dentine and cementum, are also sometimes referred to as ivory.
Density and Weight of Ivory
The density and weight of ivory depends on the species it comes from. Let’s look at some examples:
Elephant Ivory
– Density: 1.9-2.0 g/cm3
– Weight: Elephant tusks can weigh anywhere from 5 kg up to 45 kg each, with an average weight of around 9-18 kg per tusk.
Mammoth Ivory
– Density: 1.87 g/cm3
– Weight: Mammoth tusks were often larger than elephant tusks. They could weigh anywhere from 16-90 kg each.
Hippo Ivory
– Density: 1.92 g/cm3
– Weight: Hippo canine teeth typically weigh 0.5-2.5 kg each.
Walrus Ivory
– Density: 1.89-2.15 g/cm3
– Weight: Walrus tusks usually weigh 2.5-5.5 kg each.
Narwhal Ivory
– Density: 1.7-1.9 g/cm3
– Weight: The tusk of a mature male narwhal can weigh up to 10 kg.
So in summary, ivory has a density that ranges between 1.7-2.15 g/cm3 depending on the source animal. In terms of actual weight, elephant tusks are by far the heaviest source of ivory, with mammoth tusks also being extremely heavy. Walrus, hippo, and narwhal ivory weigh much less than elephant ivory per tusk but are still relatively heavy materials.
How Does the Density of Ivory Compare to Other Materials?
To better understand if ivory should be considered a heavy or light material, let’s compare its density to some other common materials:
| Material | Density (g/cm3) |
|---|---|
| Ivory (average) | 1.8-2.0 |
| Wood (oak) | 0.6-0.9 |
| Plastic | 1.0-1.5 |
| Glass | 2.4-2.8 |
| Iron | 7.8 |
| Gold | 19.3 |
Looking at this density comparison, we can see that ivory is denser and therefore heavier than common lightweight materials like wood and plastic. However, ivory is less dense and lighter than very heavy metals like iron and gold.
Compared to glass, ivory has a similar density, indicating it should have comparable weight. So while not as extremely heavy as metal, ivory is on the heavier side compared to many common materials.
The Weight of Ivory Examples
To get another perspective on whether ivory is heavy or light, let’s look at the weight of some example ivory objects:
– A carved ivory figurine measuring 5 inches tall by 2 inches wide: ~0.5 lb
– An ivory bracelet sized for a medium wrist: ~0.25 lb
– A 12 inch long solid ivory tusk section: ~2-3 lb
– A full elephant tusk measuring 8 ft long and 100 lb: ~100 lb
– A mammoth tusk measuring 6.5 ft long and 60 lb: ~60 lb
So for small ivory objects like figurines and jewelry, the weight is quite light, similar to many other materials like wood, plastic or light metals. However, for large, solid pieces like tusks, the weight quickly becomes substantial. Full ivory tusks are clearly extremely heavy.
Is Ivory Dense Enough to Sink in Water?
An interesting property of ivory is that due to its density, it will sink when placed in water, rather than floating. To demonstrate:
– Take a 1 inch cubed piece of ivory and place it in a bowl of water. It will immediately sink to the bottom.
– Do the same with a 1 inch wood cube of the same dimensions. The wood will float due to its lower density.
– Take a full solid ivory tusk section and place in water. It will rapidly sink as well.
The sinking property indicates ivory is dense and heavy enough that its weight exceeds the buoyant force of water. So in this regard, ivory can be considered a heavy, dense material compared to less dense objects that readily float.
Does Ivory’s Weight Support Its Use in Large Objects?
Historically, ivory was used to create large decorative objects like scrolls, art pieces, religious icons, and even furniture accents. A question could be – does ivory have a suitable weight and density to be worked into these large objects?
Some examples of large historical ivory pieces include:
– The Throne of Maximianus, a Byzantine throne decorated with over 120 lb of carved ivory plaques.
– The Brescia Casket, a late Roman ivory casket measuring over 3 ft long.
– The Franks Casket, an 8th century Anglo-Saxon ivory box with carved depictions of Norse myths.
– The Metz Cathedral Ivories, a collection of over 200 ivory panels used to decorate a 10th century cathedral.
For these large pieces, ivory was structurally rigid and dense enough to be carved into thin panels or decorative plaques while still maintaining their shape and attachment as architectural features. The sunk weight of the ivory helped hold pieces in place and gave them gravitas.
So in summary, ivory’s properties of rigidity and heavy, sunk weight lent themselves well to being used in large carved artistic objects and architectural features in history. Its density provided structural integrity while also producing suitably substantial-feeling works.
Is Ivory Heavy Enough to Make Effective Tools and Weapons?
In addition to decorative objects, ivory was also historically used to create tools, weapons, and hunting/fishing equipment. Did ivory have suitable properties like weight to function well for these utilitarian purposes? Some examples include:
– Ivory spear throwers from the Upper Paleolithic era.
– Mammoth ivory tribal hunting bows and arrow points.
– Early Egyptian and African iron-tipped ivory harpoons for fishing.
– 19th century European and American ivory-handled knives and guns.
– Ivory handles and structural pieces on early Chinese and Japanese swords.
For each of these tools and weapons, ivory had an optimal balance of not being too brittle, yet also having enough hardness and density to withstand impact stresses. The moderate sunk weight gave ivory pieces force and momentum when in motion as part of a tool or weapon.
So in summary, ivory had suitable hardness, toughness, and heft to be crafted into various practical implements of force and motion throughout history. But it maintained light enough weight to allow effective use as a tool material.
How Does Ivory’s Weight Factor Into Piano Keys?
A more modern application of ivory is as covering material for piano keys. This is due to its smooth, glossy surface and ability to withstand frequent impact from playing. But was ivory’s weight also a factor in its use on piano keys?
Some considerations around ivory and piano key weight:
– A standard piano has 52 white keys covered in ivory. Minimal weight per key avoids weighing down piano actions.
– Ivory covering adds smooth tactile feel without adding too much mass to keys.
– The heft from ivory can help keys rebound back to position between presses.
– Light weight prevents player fatigue versus heavier alternative cover materials.
So in summary, the low-to-moderate weight of ivory was ideal for minimizing any extra mass on piano keys. This helped maximize playability from pianists over extended performances. The rebounding heft also benefited key action.
Is Raw Ivory Easy to Work and Carve by Hand?
Historically, artisans and craftsmen worked ivory entirely by hand using simple tools like knives, chisels, drills, and abrasives. Was raw ivory actually easy to hand-work in this way?
Some factors around working raw ivory by hand:
– Ivory has slight pliability that allows carving intricate shapes without splitting.
– Sufficient density prevents crumbling or cracking during drilling and carving.
– The moderate hardness requires reasonable but not extreme force when carving manually.
– Ivory holds crisp edges and engraved details without chipping or wearing excessively from carving.
– Polishes to a fine, smooth surface when sanded as a finishing step.
So in summary, ivory had an ideal balance of density, pliability, and hardness to allow detailed and artistic hand-working into objects and art pieces. Its properties supported extended manual effort from craftsmen.
Does the Weight of Ivory Pose Challenges?
While ivory has many positive properties, are there any drawbacks or challenges presented by its weight? Some potential downsides include:
– Large tusks are extremely heavy and difficult to transport in bulk.
– Adding substantial decorative ivory can overload architectural structures.
– Ivory’s density makes items costly to ship compared to lighter materials.
– Crafting large ivory objects requires great skill to move and manipulate while carving.
– Pianos with all-ivory keys can become too heavy, affecting playability over time as key actions wear.
So in some specific applications, the heaviness and density of ivory did pose challenges around moving, structuring, and working the material. These factors likely constrained uses throughout history to some degree.
How Has Ivory Substitute Plastic Compared in Weight?
Once trade bans restricted ivory use in the 1900s, plastics emerged as an alternative for items like piano keys, billiard balls, and more. Do these plastics replicate ivory’s weight?
Some typical ivory substitute plastics:
– Cellulose acetate: Density 1.2-1.4 g/cm3
– Polyester: Density 1.2-1.4 g/cm3
– Acrylic: Density 1.1-1.2 g/cm3
Compared to ivory’s density of 1.8-2.0 g/cm3, these plastics have a 30-50% lower density and are noticeably lighter. The decreased weight made plastics favorable for high volume production of consumer goods. But some drawbacks include:
– Less gravitational heft and feel in objects like piano keys.
– Reduced durability and scratch resistance compared to ivory.
So in summary, popular ivory substitute plastics captured some of ivory’s look but were distinctly lighter in weight and feel. This made them effective for mass production but inferior in certain applications.
Conclusion
In conclusion, ivory occupies an interesting space between truly light and heavy materials in terms of density and weight. For small carved objects and thin decorative plaques, ivory has minimal weight, allowing for intricacy. Yet for full tusks and large pieces, it can be extremely heavy and substantial.
Compared to many common materials like wood, ivory is heavy and dense enough to sink in water rather than float. But it does not approach the gravity-defying heft of metals like iron or gold. So fundamentally, ivory possesses enough density and weight to be worked into art, tools, weapons, and more where its hardness and rigidity are beneficial. But its moderate heft also prevents it from being unwieldy and avoids extremes on the light/heavy scale. Ultimately, the happy balance ivory strikes between feeling sturdy and sinkable yet not overly heavy or brittle made it a uniquely versatile material historically.
