Oct 2022
The Use of Diamond Drilling in Rock and Stone Drilling

Stone carving is an expression of art used by many since the dawn of humankind. The stone’s strength, fracture toughness and abrasiveness are the main criteria for deciding how easily it can be drilled. The power of a stone depends on its mineralogical makeup. I.e. Sandstone with a high quartz content and cemented together with calcite has a low strength because the calcite that bonds the grains together is weak, whereas granite with far less quartz has high power. After all, it does not move a continuous soft phase, as does sandstone. 

You will need the right masonry to help you in your sculpting endeavour or rock drilling; for this, understanding soft and hard mediums could exponentially help you in the project you are handling. 

Utilizing the services of diamond drilling Kent in stone or rock drilling offers the advantage of modern technology, with detailing in diamond drill bits. These bits are ideal for destruction and demolition, but they are also used in stone masonry to cut into the stone and bring the artist’s vision to life. 

Characteristics for Drilling Through Stones and Rocks


Stone abrasiveness is a property that is important in drilling with diamond bits. It can affect the penetration rate and the life of the bit, controlled by its mineralogical makeup. It means that a stone with soft materials will be less abrasive than a stone with hard minerals. The hardness of the stone is measured by the ability of one mineral to scratch another, called the MOHs Hardness Scale. 

Quartz is the hardest mineral, so stones or rocks containing large quantities of quartz will be abrasive. I.e. Sandstone, which has around 60% of quartz, is far more abrasive than basalt, which contains feldspar, even though it is more potent than sandstone. 

Before you begin diamond drilling, please understand the abrasiveness of the stone you are planning to drill, as it will help you determine how well it drills and how far it can drill through. 

Strength and Fracture Toughness

This criterion reflects how easily a crack can be induced to propagate. The research on sedimentary and metamorphic rocks has shown that the strength of the rock depends on the mineralogical makeup of the stone.

Criteria For Selecting The Right Diamond Drill Bit

The correct selection of the diamond drill bit for the stone carving is essential for smooth operation. It will result in fast drilling speed, good footage, and high salvage value. The requirements for the correct diamond drill are studied considering the stone design and type.

With new research, it is now possible to select a proper matrix mix for each type of stone or rock. 

Matrix Combination

The selection of matrix mix is decided by considering the nature of the stone formation to be drilled. While drilling in hard rock requires a complex matrix when the stone has abrasive qualities. In abrasive appearance, soft matrix wears out fast, and overexposing diamond may fail. 

Essential Qualities of a Suitable Matrix 

  • It should be able to hold diamonds under all pressures of drilling.
  • Be resistant to abrasion so that stones do not get rapidly exposed. At the same time, it should be so hard that fresh stones cannot get exposed. 
  • It should be able to absorb the shock load imposed while drilling. 
  • A slow sintering temperature to avoid graphitization of diamonds with high temperature.

Recommendation for Matrix Hardness 

  • Medium Soft: Normal drilling process involving little or no abrasion – solid limestone or sandstone
  • Medium Hard: For average drilling operation, suitable for all kinds of rock or stone formations with general abrasive qualities. 
  • Hard: For highly abrasive and complex rock formation. Such as granite, quartzite, hematite or jasper.  

Diamond Grade

Generally, diamonds wear out sooner or later if they are not polished. It would be best if you had superior-quality diamond drill bits to get the optimum results. Diamond drilling Kent provides high-quality diamond drill bits for any surface drilling condition. 

Diamond Size

The formation will decide the size of the diamond it needs to drill. Smaller stones drill faster than solid rock but may also break if it has a broken build. Generally, a stone size of 60/80 stones per carat (SPC) and 80/110 SPC are used for substantial formation, while 30/60 SPC and 40/80 SPC are used in solid broken construction.

Large-size diamonds are recommended for soft stone formation as the penetration will be easier. Hence, it removes more material per revolution, but when the formation hardness increases, the number of diamonds will increase in the drilling operation for the following reasons :

  1. The more complex the rock, the smaller the size of the grain structure, and it needs slower penetration to compensate for it. Using smaller diamonds in more quantities results in more cutting points and a better penetration rate.
  2. A more significant number of diamonds distributes better pressure on the stone and rock.   


CA Drillers plan diamond distribution tracks to hold their gauge, get evenly apportioned wear, and ensure prolonged drilling life. This combined effort is possible with the help of quality manufactured drills. 

Diamond drilling Kent provides superior quality diamond drilling services, ensuring all the necessary safety measures for your projects. With four decades of industry experience, our experts know the ins and outs of diamond drilling.

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