SB 10.56.11

dine dine svarṇa-bhārān
 aṣṭau sa sṛjati prabho
durbhikṣa-māry-ariṣṭāni
 sarpādhi-vyādhayo ’śubhāḥ
na santi māyinas tatra
 yatrāste ’bhyarcito maṇiḥ
Synonyms: 
dine dine — day after day; svarṇa — of gold; bhārān — bhāras (a measure of weight); aṣṭau — eight; saḥ — it; sṛjati — would produce; prabho — O master (Parīkṣit Mahārāja); durbhikṣa — famine; māri — untimely deaths; ariṣṭāni — catastrophes; sarpa — snake (bites); ādhi — mental disorders; vyādhayaḥ — diseases; aśubhāḥ — inauspicious; na santi — there are none; māyinaḥ — cheaters; tatra — there; yatra — where; āste — it is present; abhyarcitaḥ — properly worshiped; maṇiḥ — the gem.
Translation: 
Each day the gem would produce eight bhāras of gold, my dear Prabhu, and the place in which it was kept and properly worshiped would be free of calamities such as famine or untimely death, and also of evils like snake bites, mental and physical disorders and the presence of deceitful persons.
Purport: 

Śrīla Śrīdhara Svāmī gives the following śāstric reference concerning the bhāra:

caturbhir vrīhibhir guñjāṁ
 guñjāḥ pañca paṇaṁ paṇān
aṣṭau dharaṇam aṣṭau ca
 karṣaṁ tāṁś caturaḥ palam
tulāṁ pala-śataṁ prāhur
 bhāraḥ syād viṁśatis tulāḥ

“Four rice grains are called one guñjā; five guñjās, one paṇa; eight paṇas, one karṣa; four karṣas, one pala; and one hundred palas, one tulā. Twenty tulās make up one bhāra.” Since there are about 3,700 grains of rice in an ounce, the Syamantaka jewel was producing approximately 170 pounds of gold every day.