Bukynske gabbro
In short
Bukynske gabbro is near-black. Bukynske gabbro is a dense near-black stone with a uniform fine-grained structure. It takes a deep polish and provides clear contrast for engraving.
Trade practice often calls dark stone “black granite”, but geologically gabbro and granite are different rocks. Documents should use the agreed material name rather than the word “black” alone.
Compare this stone with the others in the granite types section, and read more about sample approval in Bukynske gabbro: difference from granite and batch approval.
Specifications
| Parameter | Description |
|---|---|
| Colour | near-black |
| Finish and grain | uniform fine-grained, dense structure |
| Typical use | memorials, slabs, interiors, cladding |
| Finishes | polished above all; also honed |
| Maintenance | Regular cleaning with neutral, non-abrasive products; the exact chemistry and cleaning frequency are agreed for the finish and the location. |
Where it is used
Dense dark stone is chosen where deep contrast and an even surface are needed. It is usually applied to:
- memorials and commemorative products, including engraved work
- plates and slabs for finishing
- interior surfaces and details
- external cladding and paving slabs
Products made from this stone are collected in the catalogue: Bukynske gabbro products. Format, thickness and finish are confirmed for the specific project.
What to consider
Absolutely black stone does not occur in nature, and the tone is further changed by finish, moisture and lighting. One photograph is not enough for approval.
- Natural stone varies between blocks and cuts, so permitted differences are recorded in advance.
- Approve each required finish separately and check the sample dry and wet.
- For a large order, ask for packs to be marked by product, format and finish.
- If a batch is extended later, the new material is compared with the reference sample again.
- A dark surface shows marks clearly, so maintenance products are defined before installation.
A material name does not replace the technical brief: the suitability of a format is determined by the project, the finish and the base construction.
Physical and mechanical properties
| Property | Value | Source |
|---|---|---|
| Density | 2,780–2,950 kg/m³ (sources diverge) | ZSTU course notes, Bukynske gabbro deposit (2.78 g/cm³); kameniv.com.ua, Galant (2,950 kg/m³) |
| Water absorption | 0.05–0.11 % | ZSTU course notes (0.05–0.09 %); kameniv.com.ua, Galant (0.11 %) |
| Compressive strength | 170 MPa (ZSTU) or 280 MPa (manufacturer specification); flexural strength 50 MPa | ZSTU course notes (170 MPa); kameniv.com.ua, Galant (280 MPa compressive, 50 MPa flexural) |
| Abrasion | 0.56 g/cm² | ZSTU course notes, Bukynske gabbro deposit |
| Radiation safety class | Class 1 (unrestricted use in all types of construction) | spokij.com.ua, 'Bukynske gabbro' |
| Mineral composition | plagioclase 57–72 %, pyroxene 25–32 %, alkali feldspar 2–9 %, quartz 0–5 %, biotite 0–3 % | ZSTU course notes, Bukynske gabbro deposit |
The values are typical/reference figures for the Bukynske gabbro deposit (trade name Galant). Density and strength diverge substantially between sources (2.78 g/cm³ and 170 MPa per ZSTU versus 2,950 kg/m³ and 280 MPa per the manufacturer), so there is no agreed typical value — actual figures are confirmed by the batch certificate.
Products in this stone
Frequently asked questions
Is Bukynske gabbro a black granite?
In trade language dark stone may be called “black granite”, but geologically gabbro and granite are different rocks. Documents should use the agreed material name.
Will the whole batch be absolutely black?
No, natural stone varies. The tone is also changed by finish, moisture and lighting, so a physical sample of the current batch is required.
Does gabbro suit engraving?
Its dense fine-grained structure gives clear contrast for engraving. The specific product and the depth of work are approved from a sample.
