Digital TownsCrystalsShop crystals
  1. Crystals & Minerals
  2. Forms
  3. Towers And Obelisks

Crystal Towers and Obelisks: How They Are Cut and Judged

By Digital Towns Crystals ยท Last reviewed October 8, 2026

Short answer: a tower is a block of stone sawn and ground into a standing column with a faceted tip; an obelisk is the same idea with four tapering sides and a small pyramid on top; a "generator" is trade slang for a six-sided tower whose tip faces meet in one point. All three are lapidary work. Judge them on a centered apex, straight edges, an even polish without haze or scratches, a square base, and a material hard enough to keep its tip.

What is the difference between a tower, an obelisk and a generator?

The names describe cut geometry, not minerals.

  • Tower (or polished point): usually six sides, sometimes more, rising from a flat base to a faceted tip. Proportions vary from squat to slender.
  • Obelisk: four sides that taper toward the top, finished with a short four-faced pyramid, copying the stone monuments of ancient Egypt.
  • Generator: a dealer's term for a tower, often quartz, with six even sides and six tip faces meeting at a single sharp apex. In crystal traditions the shape is associated with gathering and focusing intention; that is a belief about the form, not a property of the stone.

Because the shape is cut, almost any material can be made into one, from clear quartz to banded jasper, which is why tower racks are often the most varied shelf in a shop. Whether a tower keeps its natural faces anywhere is covered in the natural vs polished points guide.

How is a crystal tower cut?

The process uses the same machines a cabochon or sphere cutter uses, scaled up. Large commercial workshops run it as a production line, but the steps do not change.

1. Reading the rough

A cutter studies the block for fractures, color zones and inclusions before sawing. Fractures decide where the column can go; a crack that runs across the finished tip will snap it later. For banded or zoned material, the cutter decides which way the bands should run, usually lengthwise or across the column for drama.

2. Sawing the blank

Rough is cut into a rectangular blank on a diamond saw. According to the International Gem Society, trim saws use 4" to 6" blades between .004" and .012" thick, while slab saw blades run from 6" to 36" with thicknesses of .025" to .200". Large obelisks start on slab saws. Saws run with oil or water coolant; the IGS recommends oil designed specifically for lapidary use for slab saws.

3. Grinding the sides and tip

The blank is ground into its sides on coarse wheels or flat laps, then the tip faces are ground on at an angle. This is where skill shows: every side must stay the same width so the edges stay straight, and every tip face must meet the others at one point. Water serves as a lubricant during grinding, keeping friction and heat down and carrying away the cutting debris, called swarf, as the IGS cabochon cutting guide explains.

4. Sanding and polishing

Scratches from coarse grinding are removed in stages. For cabochons the IGS cites a typical sequence of 260, 600 and 1,200 grit diamond, and towers go through a similar ladder. The final polish depends on the stone: the same guide notes that quartz responds best to cerium oxide, and that heat builds quickly during polishing, which matters for heat-sensitive material.

5. Truing the base

The bottom is ground flat and square so the tower stands upright without rocking. On a good piece the base is fine-sanded too; on a cheap one it is left rough from the saw.

An old trade

Idar-Oberstein in Germany has cut stone since the Middle Ages. The IGS history of laps and polish records that its cutters began working on waterwheel-powered mills toward the end of the 1200s, and that its sandstone cutting mills were pioneered for cutting agate and quartz. The diamond wheels in a modern tower workshop are descendants of that equipment.

Which stones make good towers, and which chip?

A tower tip is a sharp point on a long lever, so hardness and cleavage decide how it ages.

Material Mohs hardness Weak point Tower behaviour
Quartz (clear, smoky, amethyst) 7 No cleavage Holds a crisp tip; the most durable common choice
Obsidian About 5.5 Low toughness Polishes to a mirror but chips on impact
Fluorite 4 Four directions of perfect cleavage Tips and edges flake along cleavage planes
Calcite 3 Three rhombohedral cleavages Scratches easily; edges round with handling
Lapis lazuli 3 to 6.5 depending on the mineral tested Mixed rock Polish can be uneven across calcite and lazurite

The numbers come from Geology.com, which notes fluorite is the only common mineral with four directions of perfect cleavage, and from its pages on calcite and obsidian; the obsidian page adds that the glass lacks toughness and is easily broken or chipped upon impact. For lapis, Geology.com explains that hardness ranges from a Mohs 3 for calcite to the 6.5 of pyrite, so the polish quality depends on where the cutter is working.

Soft stones still make beautiful towers. Fluorite towers show banding that no other material matches, and calcite glows in lamplight. Treat them as display pieces, not handling pieces.

How do you judge the quality of a tower?

Stand it on a flat surface at eye level and turn it slowly.

  • Apex: the tip faces should meet at one point, centered over the base. A tip that ends in a short ridge or leans to one side shows rushed grinding.
  • Edges: each vertical edge should be straight from base to tip. Wavy edges mean uneven sides.
  • Polish: look at a reflected window or lamp in each face. A sharp reflection means a full polish; a blurred or dimpled reflection (sometimes called orange peel) means it was polished too fast. Fine parallel scratches mean a sanding stage was skipped.
  • Undercutting: on stones with soft and hard zones, such as lapis or jasper, softer patches wear lower than the rest and show as shallow dips.
  • Fractures and fills: cracks reaching the surface collect dirt and may hide resin. Run a fingernail across them.
  • Treatments: Geology.com reports that much lapis entering the market is dyed blue to hide white calcite, then treated with wax or oil to seal the dye. A cotton swab with acetone touched to the base can lift color from dyed material.
  • Base: square, flat and finished. A tower that rocks will eventually fall.

What drives the price of a tower or obelisk?

Material first. A clear quartz tower is cheap per kilogram until it gets large and clean: the IGS notes that rock crystal is common and has little intrinsic value except in very large, flawless pieces, while also being prized by carvers. That is why a 17 inch clear obelisk costs a hundred times more than a palm-size one. Rarer materials with phantoms, strong banding or visible inclusions sit higher. Then come size and weight, the quality of the cut, and whether natural features such as phantoms were placed well within the column. Hand-finished pieces with crisp geometry cost more than tumbled-edge production work in the same stone.

Shopping the towers and obelisks we stock

Decide whether the piece will be handled or only displayed, then choose a material to match. For a desk tower that will be picked up, quartz is the safe choice. For a showpiece, judge the geometry and polish using the checks above, and ask for a photo of the base.

Digital Towns Market

Towers and obelisks in stock

See all crystals and minerals

Frequently asked questions

Are crystal towers natural formations?

No. Towers and obelisks are cut from larger rough. Some quartz towers keep a patch of natural crystal face, and some are cut from a single crystal, but the column and tip are shaped by a lapidary.

Why did the tip of my fluorite tower chip?

Fluorite has a hardness of 4 and four directions of perfect cleavage, so a light knock can split a flake off along a cleavage plane. Keep fluorite towers away from edges and harder stones.

What is the difference between a tower and a generator?

Generator is a trade term for a tower, often quartz, with six even sides and six tip faces meeting at a single point. Every generator is a tower, but many towers have other side counts or uneven tips.

How should I clean a polished tower?

Wipe hard stones such as quartz with a damp soft cloth and dry them. Keep soft or porous material such as calcite, fluorite and dyed lapis away from soaking, solvents and abrasive cloths, which can dull the polish or lift dye.

How can I tell a well-cut tower from a poor one?

Look for a centered apex where all tip faces meet in one point, straight edges, a sharp mirror reflection in every face, no fine scratches, and a flat base that does not rock.

Sources