Gondwana coal

Topic: Energy Resources of India: Conventional and Non-conventional · NCERT: Class 10, Ch 5 "Minerals and Energy Resources"; Class 12, Ch 5 "Mineral and Energy Resources"

Meaning

Gondwana coal is coal that formed about 250–300 million years ago (Permian period) in long, sunken troughs along old river valleys of Gondwanaland. Today it lies in the Gondwana rock basins of eastern and central Peninsular India. It makes up about 99.6% of India's coal resources and includes all of India's coking coal [2]. So it is the main base of India's thermal power and steel industries.

Explanation

How it formed (cause → process → result)

• Cause: India was once part of Gondwanaland. This was an old southern super-continent that also included Africa, Australia, South America and Antarctica.
• Long, sunken troughs formed along old river valleys.

• Thick swamp forests grew in these troughs.

• Process:

• Dead plants sank into wet mud that had no air, so they did not fully rot.
• Rivers laid more mud and sand on top. The plant mass was pressed down and buried deeper.

• Deeper down, heat and pressure squeezed out water and gases, so the share of carbon went up. This change is called organic maturity (how far heat, pressure and time have changed the plant material) [3].

• Result: mostly bituminous coal ("hard coal"). It is high in carbon and gives good heat.

• Age: about 250–300 million years. NCERT Class 10 says "a little over 200 million years".

Types within Gondwana coal

• Coking coal (metallurgical coal): high-grade bituminous coal. When heated without air it turns into coke (a hard, porous fuel). Coke is used in blast furnaces (tall furnaces that smelt iron ore into iron).
• Prime coking: 5,443.41 MT. Medium coking: 30,132.09 MT. Semi-coking: 1,797.48 MT (01.04.2025) [2].

• Total: 37,372.98 MT, only about 9.3% of all coal resources [2]. It is found mainly at Jharia.

• Non-coking coal: burnt in thermal power stations (plants that burn coal to make steam and electricity), and in cement and sponge-iron plants.

• Gondwana non-coking resources: 3,61,647.82 MT, about 90% of the total (01.04.2025) [2].
• Non-coking coal is graded G1–G17 by heat value. Inferior grades (G7–G17) make up 2,93,130.31 MT, about 73% of all coal [2].

Quality: high ash, low sulphur

• Ash is the rock and mineral matter left after coal burns.

• More ash means less heat, more fly-ash waste and more wear on boilers.

• Gondwana coal is high-ash, often 30–45%.

• Why: as the plants settled, they mixed with river mud and sand. That mineral matter stayed in the coal.
• Washing helps only partly. A washery is a plant that cleans coal to remove ash.
• Raw coal sent to washeries: 24–33% ash [3].

• After washing, clean coal has 19–22% ash, middlings have 35–40%, and rejects have over 50% [3].

• Sulphur is low. This is the main advantage Gondwana coal has over Tertiary coal.

Size of the resource (01.04.2025)

• Gondwana coal: 3,99,020.80 MT out of a total of 4,00,715.45 MT [2].
• The count includes coal down to 1,200 m depth, in seams 0.90 m or thicker [2].
• NCERT gives the older figure of about 98%.
• The inventory is prepared by the Geological Survey of India (GSI) [2].

Where it occurs

• Damodar valley (Jharkhand–West Bengal), the most important belt:
• Jharia: the largest coalfield, with coking coal
• Raniganj: the second largest

• Bokaro, Giridih, Karanpura

• Mahanadi valley (Odisha): Talcher and Ib Valley, mined by MCL (Mahanadi Coalfields Ltd) [3]. Korba (Chhattisgarh) is also in this basin.

• Son valley: Singrauli, on the Madhya Pradesh–Uttar Pradesh border.
• Godavari and Wardha valleys (Telangana, Maharashtra):
• SCCL (Singareni Collieries, Telangana) produces non-coking coal.

• It supplies most of South India's coal users [3].

• Outside the Peninsula: small amounts in Assam and Sikkim [3].

• Coal resources by state, highest first (01.04.2025) [2]:
• Odisha 1,00,975.78 MT
• Jharkhand 93,254.06 MT
• Chhattisgarh 85,263.22 MT
• West Bengal 34,386.09 MT
• Madhya Pradesh 33,563.62 MT
• Telangana 23,288.62 MT
• Maharashtra 13,586.70 MT

• Bihar 9,353.44 MT

• In the world: other parts of old Gondwanaland, such as Australia, also have coal of this age. India imports much of its coking coal from Australia.

Don't confuse with

• Tertiary coal: much younger (about 15–60 million years). It is found in Assam, Arunachal Pradesh, Nagaland, Meghalaya [3] and Kalakot (J&K). It is low-ash with high heat value, but high in sulphur, so it cannot be used directly as metallurgical coal [3]. Gondwana coal is the opposite: high-ash and low-sulphur.
• Lignite: soft brown coal in Tertiary rocks. Neyveli (Cuddalore, Tamil Nadu) is the largest deposit. Lignite is not Gondwana coal, and its resources (about 47,370.54 MT) are counted separately [2].
• Anthracite: the highest grade of hard coal. India has very little, mainly in Jammu and Kashmir. Gondwana coal is mostly bituminous, not anthracite.
• Coking vs non-coking: all of India's coking coal is Gondwana coal, but most Gondwana coal is non-coking (about 90% of the total) [2].

Prelims Hooks

• Gondwana coal is about 99.6% of India's coal resources (3,99,020.80 MT of 4,00,715.45 MT, 01.04.2025). NCERT says about 98% [2].
• Jharia (Damodar valley, Jharkhand) is the largest coalfield and the main source of coking coal. Raniganj (West Bengal) is the second largest.
• Field–valley pairs: Talcher, Ib Valley → Mahanadi. Singrauli → Son. Singareni → Godavari. Jharia, Bokaro, Giridih, Karanpura → Damodar.
• State order, highest first: Odisha > Jharkhand > Chhattisgarh > West Bengal > Madhya Pradesh [2].
• Trap: Gondwana coal is high-ash, low-sulphur. Tertiary coal is low-ash, high-sulphur [3].
• Coking coal is only about 9.3% of resources, so India imports it for steel, mainly from Australia [2].

Mains Points

• Distribution shapes industry (GS-I): Gondwana coal is packed into the Damodar, Mahanadi, Son and Godavari–Wardha valleys [2][3].
• So: steel and thermal power plants cluster in the Chota Nagpur–Odisha belt.

• But: the North-West and South depend on long-distance rail transport of coal, or on local lignite.

• Plenty of coal, but poor quality (GS-III): about 73% of resources are inferior grades (G7–G17), and coking coal is only about 9.3% [2]. Raw coal ash is 24–33% [3].

• So: India imports coking coal under Open General Licence (no special permit needed) [3].

• Response: coal washeries and blending to stretch home supplies [3].

• Energy security vs environment (GS-III): coal generates about 72% of India's electricity [3]. Production reached 1,047.52 MT in 2024-25 [2].

• High-ash Gondwana coal leaves huge piles of fly ash.
• This is one reason India is moving towards non-fossil capacity, while coal stays its main home-grown fuel.

Related concepts

• Coal
• Anthracite
• Bituminous coal
• Coking coal
• Tertiary coal
• Lignite
• Neyveli lignite

Read more

• Coal: formation, grades and the Gondwana-Tertiary divide